project: add TransportConfig.swift to Share Extension target to fix build

Add comprehensive TransportConfig constants for UI, Nostr, and BLE; adopt across ChatViewModel, ContentView, BLEService, ShareViewController, and BitchatApp to remove scattered literals. Standardize Nostr lookbacks/limits, UI delays/animations, and BLE announce/duty-cycle/candidate caps. Preserve behavior while making tuning explicit and safe.

Highlights:\n- UI: animations, scroll throttle, long-message thresholds, batch stagger, color hue tuning, rate-limit buckets, read-receipt debounce, startup delays, share accept/dismiss windows, migration cutoff.\n- Nostr: short display length (8), conv-key prefix length (16), DM lookback (24h), geohash sample lookback/limits; consistent use throughout ChatViewModel.\n- BLE: dynamic RSSI defaults, announce intervals/base+jitter, duty cycles (dense/sparse), fragment/ingress lifetimes, expected write timings/spacing, recent packet window (30s/100), peer inactivity timeout; unified candidate caps (100).\n- Share: use constant dismiss delay; App: use constant share accept window.\n\nRisk/impact: behavior-equivalent with centralized knobs; easier to tune without code edits.

bitchat.xcodeproj/project.pbxproj

@@ -17,7 +17,6 @@
 		0475028D2E54171C0083520F /* LocationChannelManager.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0475028B2E54171C0083520F /* LocationChannelManager.swift */; };
 		0475028F2E5417660083520F /* LocationChannelsSheet.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0475028E2E5417660083520F /* LocationChannelsSheet.swift */; };
 		047502902E5417660083520F /* LocationChannelsSheet.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0475028E2E5417660083520F /* LocationChannelsSheet.swift */; };
-
 		047502922E547ACC0083520F /* LocationChannelsTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 047502912E547ACC0083520F /* LocationChannelsTests.swift */; };
 		047502932E547ACC0083520F /* LocationChannelsTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 047502912E547ACC0083520F /* LocationChannelsTests.swift */; };
 		047502AC2E55E8360083520F /* BinaryProtocolPaddingTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 047502AB2E55E8360083520F /* BinaryProtocolPaddingTests.swift */; };
@@ -30,6 +29,9 @@
 		047502B72E55FED60083520F /* GeohashPeopleList.swift in Sources */ = {isa = PBXBuildFile; fileRef = 047502B22E55FED60083520F /* GeohashPeopleList.swift */; };
 		047502B92E560F690083520F /* RelayController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 047502B82E560F690083520F /* RelayController.swift */; };
 		047502BA2E560F690083520F /* RelayController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 047502B82E560F690083520F /* RelayController.swift */; };
+		048A4BE72E5CCCC300162C4A /* TransportConfig.swift in Sources */ = {isa = PBXBuildFile; fileRef = 048A4BE62E5CCCC300162C4A /* TransportConfig.swift */; };
+		048A4BE82E5CCCC300162C4A /* TransportConfig.swift in Sources */ = {isa = PBXBuildFile; fileRef = 048A4BE62E5CCCC300162C4A /* TransportConfig.swift */; };
+		048A4BE92E5CCCC300162C4B /* TransportConfig.swift in Sources */ = {isa = PBXBuildFile; fileRef = 048A4BE62E5CCCC300162C4A /* TransportConfig.swift */; };
 		049BD3902E4EC4F0001A566B /* PrivateChatManager.swift in Sources */ = {isa = PBXBuildFile; fileRef = 049BD38F2E4EC4F0001A566B /* PrivateChatManager.swift */; };
 		049BD3912E4EC4F0001A566B /* AutocompleteService.swift in Sources */ = {isa = PBXBuildFile; fileRef = 049BD38C2E4EC4F0001A566B /* AutocompleteService.swift */; };
 		049BD3922E4EC4F0001A566B /* CommandProcessor.swift in Sources */ = {isa = PBXBuildFile; fileRef = 049BD38D2E4EC4F0001A566B /* CommandProcessor.swift */; };
@@ -57,6 +59,8 @@
 		0AE840940F21AFC07C226636 /* PrivateChatE2ETests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 8A262EDDC04B7D7B5E31F321 /* PrivateChatE2ETests.swift */; };
 		0B6F25559A21F8C69C8357C6 /* BinaryProtocolTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0B3CC6FA298729906109F61B /* BinaryProtocolTests.swift */; };
 		10E68BB889356219189E38EC /* BitchatApp.swift in Sources */ = {isa = PBXBuildFile; fileRef = EF625BB3AD919322C01A46B2 /* BitchatApp.swift */; };
+		1234567890ABCDEFFEDCBA13 /* PeerDisplayNameResolver.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1234567890ABCDEFFEDCBA02 /* PeerDisplayNameResolver.swift */; };
+		1234567890ABCDEFFEDCBA14 /* PeerDisplayNameResolver.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1234567890ABCDEFFEDCBA02 /* PeerDisplayNameResolver.swift */; };
 		132DF1E24B4E9C7DCDAD4376 /* FingerprintView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9195CDC7EB236AFBC9A4D41A /* FingerprintView.swift */; };
 		17901751FD8010AFC8E750F2 /* bitchatShareExtension.appex in Embed Foundation Extensions */ = {isa = PBXBuildFile; fileRef = 61F92EBA29C47C0FCC482F1F /* bitchatShareExtension.appex */; settings = {ATTRIBUTES = (RemoveHeadersOnCopy, ); }; };
 		1D9674FA5F998503831DC281 /* ContentView.swift in Sources */ = {isa = PBXBuildFile; fileRef = A08E03AA0C63E97C91749AEC /* ContentView.swift */; };
@@ -103,11 +107,17 @@
 		9C7D287C8E67AAE576A5ECB7 /* ShareViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = C1B378C16594575FCC7F9C75 /* ShareViewController.swift */; };
 		9CCF09F7527EC681A13FC246 /* NoiseSecurityConsiderations.swift in Sources */ = {isa = PBXBuildFile; fileRef = 43B4548DAFC9F7AA8873DA53 /* NoiseSecurityConsiderations.swift */; };
 		A0A1C26EFBFDD5B8EFEEDE57 /* PublicChatE2ETests.swift in Sources */ = {isa = PBXBuildFile; fileRef = D22BF09A49010947CEFE45E2 /* PublicChatE2ETests.swift */; };
+		A1B2C3D44E5F60718293A4B5 /* XChaCha20Poly1305Compat.swift in Sources */ = {isa = PBXBuildFile; fileRef = A1B2C3D44E5F60718293A4B4 /* XChaCha20Poly1305Compat.swift */; };
+		A1B2C3D54E5F60718293A4B6 /* XChaCha20Poly1305Compat.swift in Sources */ = {isa = PBXBuildFile; fileRef = A1B2C3D44E5F60718293A4B4 /* XChaCha20Poly1305Compat.swift */; };
 		A2977428C1D9EF9944C4BFAF /* BLEServiceTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 980B109CBA72BC996455C62B /* BLEServiceTests.swift */; };
 		A7187D48B07C6857DE01D0ED /* NoiseProtocol.swift in Sources */ = {isa = PBXBuildFile; fileRef = 43613045E63D21D429396805 /* NoiseProtocol.swift */; };
 		AA11BB22CC33DD44EE55FF66 /* MessageTextHelpers.swift in Sources */ = {isa = PBXBuildFile; fileRef = AA11BB22CC33DD44EE55FF68 /* MessageTextHelpers.swift */; };
 		AA11BB22CC33DD44EE55FF67 /* MessageTextHelpers.swift in Sources */ = {isa = PBXBuildFile; fileRef = AA11BB22CC33DD44EE55FF68 /* MessageTextHelpers.swift */; };
 		AA6E067DB034FC0FA23C28A9 /* BinaryProtocolTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0B3CC6FA298729906109F61B /* BinaryProtocolTests.swift */; };
+		AA77BB11CC22DD33EE44FF55 /* VerificationService.swift in Sources */ = {isa = PBXBuildFile; fileRef = AA77BB10CC22DD33EE44FF55 /* VerificationService.swift */; };
+		AA77BB12CC22DD33EE44FF56 /* VerificationService.swift in Sources */ = {isa = PBXBuildFile; fileRef = AA77BB10CC22DD33EE44FF55 /* VerificationService.swift */; };
+		AA77BB14CC22DD33EE44FF58 /* VerificationViews.swift in Sources */ = {isa = PBXBuildFile; fileRef = AA77BB13CC22DD33EE44FF57 /* VerificationViews.swift */; };
+		AA77BB15CC22DD33EE44FF59 /* VerificationViews.swift in Sources */ = {isa = PBXBuildFile; fileRef = AA77BB13CC22DD33EE44FF57 /* VerificationViews.swift */; };
 		ABAF130D88561F4A646F0430 /* AppInfoView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 763E0DBA9492A654FC0CDCB9 /* AppInfoView.swift */; };
 		ACE2ED172C37F01561E50B71 /* FavoritesPersistenceService.swift in Sources */ = {isa = PBXBuildFile; fileRef = 419BFFF209EBA93F410E9E9F /* FavoritesPersistenceService.swift */; };
 		AD11E46940D742AEAF547EB2 /* AppInfoView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 763E0DBA9492A654FC0CDCB9 /* AppInfoView.swift */; };
@@ -141,12 +151,6 @@
 		F455F011B3B648ADA233F998 /* BinaryProtocol.swift in Sources */ = {isa = PBXBuildFile; fileRef = A2136C3E22D02D4A8DBE7EAB /* BinaryProtocol.swift */; };
 		FB8819B4C84FAFEF5C36B216 /* KeychainManager.swift in Sources */ = {isa = PBXBuildFile; fileRef = 136696FC4436A02D98CE6A77 /* KeychainManager.swift */; };
 		FBC409E105493C491531B59A /* NostrProtocol.swift in Sources */ = {isa = PBXBuildFile; fileRef = 2E5A9FF4AEA8A923317ED26A /* NostrProtocol.swift */; };
-		A1B2C3D44E5F60718293A4B5 /* XChaCha20Poly1305Compat.swift in Sources */ = {isa = PBXBuildFile; fileRef = A1B2C3D44E5F60718293A4B4 /* XChaCha20Poly1305Compat.swift */; };
-		A1B2C3D54E5F60718293A4B6 /* XChaCha20Poly1305Compat.swift in Sources */ = {isa = PBXBuildFile; fileRef = A1B2C3D44E5F60718293A4B4 /* XChaCha20Poly1305Compat.swift */; };
-		AA77BB11CC22DD33EE44FF55 /* VerificationService.swift in Sources */ = {isa = PBXBuildFile; fileRef = AA77BB10CC22DD33EE44FF55 /* VerificationService.swift */; };
-		AA77BB12CC22DD33EE44FF56 /* VerificationService.swift in Sources */ = {isa = PBXBuildFile; fileRef = AA77BB10CC22DD33EE44FF55 /* VerificationService.swift */; };
-		AA77BB14CC22DD33EE44FF58 /* VerificationViews.swift in Sources */ = {isa = PBXBuildFile; fileRef = AA77BB13CC22DD33EE44FF57 /* VerificationViews.swift */; };
-		AA77BB15CC22DD33EE44FF59 /* VerificationViews.swift in Sources */ = {isa = PBXBuildFile; fileRef = AA77BB13CC22DD33EE44FF57 /* VerificationViews.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -200,6 +204,7 @@
 		047502B22E55FED60083520F /* GeohashPeopleList.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = GeohashPeopleList.swift; sourceTree = "<group>"; };
 		047502B32E55FED60083520F /* MeshPeerList.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MeshPeerList.swift; sourceTree = "<group>"; };
 		047502B82E560F690083520F /* RelayController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RelayController.swift; sourceTree = "<group>"; };
+		048A4BE62E5CCCC300162C4A /* TransportConfig.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TransportConfig.swift; sourceTree = "<group>"; };
 		049BD38C2E4EC4F0001A566B /* AutocompleteService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AutocompleteService.swift; sourceTree = "<group>"; };
 		049BD38D2E4EC4F0001A566B /* CommandProcessor.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CommandProcessor.swift; sourceTree = "<group>"; };
 		049BD38F2E4EC4F0001A566B /* PrivateChatManager.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PrivateChatManager.swift; sourceTree = "<group>"; };
@@ -215,6 +220,7 @@
 		05BA20BC0F123F1507C5C247 /* IdentityModels.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = IdentityModels.swift; sourceTree = "<group>"; };
 		0B3CC6FA298729906109F61B /* BinaryProtocolTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BinaryProtocolTests.swift; sourceTree = "<group>"; };
 		11186E29A064E8D210880E1B /* BitchatPeer.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BitchatPeer.swift; sourceTree = "<group>"; };
+		1234567890ABCDEFFEDCBA02 /* PeerDisplayNameResolver.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PeerDisplayNameResolver.swift; sourceTree = "<group>"; };
 		136696FC4436A02D98CE6A77 /* KeychainManager.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeychainManager.swift; sourceTree = "<group>"; };
 		229F17B68CFF7AB1BC91C847 /* BitchatProtocol.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BitchatProtocol.swift; sourceTree = "<group>"; };
 		2E346DF8E026FD34EE3DD038 /* TestHelpers.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TestHelpers.swift; sourceTree = "<group>"; };
@@ -245,9 +251,11 @@
 		980B109CBA72BC996455C62B /* BLEServiceTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BLEServiceTests.swift; sourceTree = "<group>"; };
 		9AB6BE4ABD7F5088E9865E56 /* NoiseSession.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NoiseSession.swift; sourceTree = "<group>"; };
 		A08E03AA0C63E97C91749AEC /* ContentView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ContentView.swift; sourceTree = "<group>"; };
+		A1B2C3D44E5F60718293A4B4 /* XChaCha20Poly1305Compat.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = XChaCha20Poly1305Compat.swift; sourceTree = "<group>"; };
 		A2136C3E22D02D4A8DBE7EAB /* BinaryProtocol.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BinaryProtocol.swift; sourceTree = "<group>"; };
-
 		AA11BB22CC33DD44EE55FF68 /* MessageTextHelpers.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MessageTextHelpers.swift; sourceTree = "<group>"; };
+		AA77BB10CC22DD33EE44FF55 /* VerificationService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = VerificationService.swift; sourceTree = "<group>"; };
+		AA77BB13CC22DD33EE44FF57 /* VerificationViews.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = VerificationViews.swift; sourceTree = "<group>"; };
 		B1D6A89B36A3D31E590B94E5 /* NoiseHandshakeCoordinator.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NoiseHandshakeCoordinator.swift; sourceTree = "<group>"; };
 		C0DB1DE27F0AAB5092663E8E /* bitchatTests_iOS.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = bitchatTests_iOS.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		C1B378C16594575FCC7F9C75 /* ShareViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ShareViewController.swift; sourceTree = "<group>"; };
@@ -266,9 +274,6 @@
 		FDC18D910D6FF2E8B1B6C885 /* SecureIdentityStateManager.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SecureIdentityStateManager.swift; sourceTree = "<group>"; };
 		FE7CCF2BD78A3F3DAE6DA145 /* MockBLEService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MockBLEService.swift; sourceTree = "<group>"; };
 		FF7AF93D874001FBD94C8306 /* bitchat-macOS.entitlements */ = {isa = PBXFileReference; lastKnownFileType = text.plist.entitlements; path = "bitchat-macOS.entitlements"; sourceTree = "<group>"; };
-		A1B2C3D44E5F60718293A4B4 /* XChaCha20Poly1305Compat.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = XChaCha20Poly1305Compat.swift; sourceTree = "<group>"; };
-		AA77BB10CC22DD33EE44FF55 /* VerificationService.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = VerificationService.swift; sourceTree = "<group>"; };
-		AA77BB13CC22DD33EE44FF57 /* VerificationViews.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = VerificationViews.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -323,6 +328,7 @@
 				A2E8C336FA1ADBEC03261DFD /* bitchatShareExtension */,
 				C3D98EB3E1B455E321F519F4 /* bitchatTests */,
 				9F37F9F2C353B58AC809E93B /* Products */,
+				048A4BE52E5CCC5C00162C4A /* Recovered References */,
 			);
 			sourceTree = "<group>";
 		};
@@ -405,6 +411,7 @@
 		9A78348821A7D3374607D4E3 /* Utils */ = {
 			isa = PBXGroup;
 			children = (
+				1234567890ABCDEFFEDCBA02 /* PeerDisplayNameResolver.swift */,
 				049BD3AA2E51E38E001A566B /* PeerIDResolver.swift */,
 				049BD3A42E51DC0E001A566B /* MessageDeduplicator.swift */,
 				32F149C43D1915831B60FE09 /* CompressionUtil.swift */,
@@ -443,7 +450,6 @@
 				047502B22E55FED60083520F /* GeohashPeopleList.swift */,
 				047502B32E55FED60083520F /* MeshPeerList.swift */,
 				0475028E2E5417660083520F /* LocationChannelsSheet.swift */,
-
 				763E0DBA9492A654FC0CDCB9 /* AppInfoView.swift */,
 				A08E03AA0C63E97C91749AEC /* ContentView.swift */,
 				9195CDC7EB236AFBC9A4D41A /* FingerprintView.swift */,
@@ -514,6 +520,7 @@
 		D98A3186D7E4C72E35BDF7FE /* Services */ = {
 			isa = PBXGroup;
 			children = (
+				048A4BE62E5CCCC300162C4A /* TransportConfig.swift */,
 				AA77BB10CC22DD33EE44FF55 /* VerificationService.swift */,
 				047502B82E560F690083520F /* RelayController.swift */,
 				0475028B2E54171C0083520F /* LocationChannelManager.swift */,
@@ -727,6 +734,7 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				048A4BE92E5CCCC300162C4B /* TransportConfig.swift in Sources */,
 				9C7D287C8E67AAE576A5ECB7 /* ShareViewController.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -735,11 +743,14 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+                048A4BE72E5CCCC300162C4A /* TransportConfig.swift in Sources */,
+                1234567890ABCDEFFEDCBA13 /* PeerDisplayNameResolver.swift in Sources */,
 				AA77BB12CC22DD33EE44FF56 /* VerificationService.swift in Sources */,
 				AA77BB15CC22DD33EE44FF59 /* VerificationViews.swift in Sources */,
 				A1B2C3D54E5F60718293A4B6 /* XChaCha20Poly1305Compat.swift in Sources */,
 				AD11E46940D742AEAF547EB2 /* AppInfoView.swift in Sources */,
 				9B51E9B63A3EA59B1A7874BD /* BinaryEncodingUtils.swift in Sources */,
+
 				049BD3B42E51F319001A566B /* NostrTransport.swift in Sources */,
 				049BD3B52E51F319001A566B /* MessageRouter.swift in Sources */,
 				4B747085D07A1BCE0F5BA612 /* BinaryProtocol.swift in Sources */,
@@ -758,7 +769,6 @@
 				7241FFD6CFFB875B864FA223 /* InputValidator.swift in Sources */,
 				FB8819B4C84FAFEF5C36B216 /* KeychainManager.swift in Sources */,
 				0475028F2E5417660083520F /* LocationChannelsSheet.swift in Sources */,
-
 				501BC56B1A08C0327A09AAF1 /* NoiseEncryptionService.swift in Sources */,
 				0475028C2E54171C0083520F /* LocationChannelManager.swift in Sources */,
 				AFF33EF44626EF0579D17EB1 /* NoiseHandshakeCoordinator.swift in Sources */,
@@ -793,11 +803,14 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+                048A4BE82E5CCCC300162C4A /* TransportConfig.swift in Sources */,
+                1234567890ABCDEFFEDCBA14 /* PeerDisplayNameResolver.swift in Sources */,
 				AA77BB11CC22DD33EE44FF55 /* VerificationService.swift in Sources */,
 				AA77BB14CC22DD33EE44FF58 /* VerificationViews.swift in Sources */,
 				A1B2C3D44E5F60718293A4B5 /* XChaCha20Poly1305Compat.swift in Sources */,
 				ABAF130D88561F4A646F0430 /* AppInfoView.swift in Sources */,
 				AFB6AEFCABBE97441CB3102B /* BinaryEncodingUtils.swift in Sources */,
+
 				049BD3B22E51F319001A566B /* NostrTransport.swift in Sources */,
 				049BD3B32E51F319001A566B /* MessageRouter.swift in Sources */,
 				F455F011B3B648ADA233F998 /* BinaryProtocol.swift in Sources */,
@@ -816,7 +829,6 @@
 				EF49C600C1E464710DD6CA29 /* InputValidator.swift in Sources */,
 				8F737CE0435792CC2AD65FCB /* KeychainManager.swift in Sources */,
 				047502902E5417660083520F /* LocationChannelsSheet.swift in Sources */,
-
 				5EE49E150BBF0488E7473687 /* NoiseEncryptionService.swift in Sources */,
 				0475028D2E54171C0083520F /* LocationChannelManager.swift in Sources */,
 				6D0D4A0B1D8B659DCBAE7C9C /* NoiseHandshakeCoordinator.swift in Sources */,

bitchat/BitchatApp.swift

@@ -99,15 +99,15 @@ struct BitchatApp: App {
             return
         }
         
-        // Only process if shared within last 30 seconds
+        // Only process if shared within configured window
-        if Date().timeIntervalSince(sharedDate) < 30 {
+        if Date().timeIntervalSince(sharedDate) < TransportConfig.uiShareAcceptWindowSeconds {
             let contentType = userDefaults.string(forKey: "sharedContentType") ?? "text"
             
             // Clear the shared content
             userDefaults.removeObject(forKey: "sharedContent")
             userDefaults.removeObject(forKey: "sharedContentType")
             userDefaults.removeObject(forKey: "sharedContentDate")
-            userDefaults.synchronize()
+            // No need to force synchronize here
             
             // Send the shared content immediately on the main queue
             DispatchQueue.main.async {

bitchat/Nostr/GeoRelayDirectory.swift

@@ -14,7 +14,7 @@ final class GeoRelayDirectory {
     private let cacheFileName = "georelays_cache.csv"
     private let lastFetchKey = "georelay.lastFetchAt"
     private let remoteURL = URL(string: "https://raw.githubusercontent.com/permissionlesstech/georelays/refs/heads/main/nostr_relays.csv")!
-    private let fetchInterval: TimeInterval = 60 * 60 * 24 // 24h
+    private let fetchInterval: TimeInterval = TransportConfig.geoRelayFetchIntervalSeconds // 24h
 
     private init() {
         // Load cached or bundled data synchronously

bitchat/Nostr/NostrRelayManager.swift

@@ -48,10 +48,10 @@ class NostrRelayManager: ObservableObject {
     private let messageQueueLock = NSLock()
     
     // Exponential backoff configuration
-    private let initialBackoffInterval: TimeInterval = 1.0  // Start with 1 second
+    private let initialBackoffInterval: TimeInterval = TransportConfig.nostrRelayInitialBackoffSeconds
-    private let maxBackoffInterval: TimeInterval = 300.0    // Max 5 minutes
+    private let maxBackoffInterval: TimeInterval = TransportConfig.nostrRelayMaxBackoffSeconds
-    private let backoffMultiplier: Double = 2.0            // Double each time
+    private let backoffMultiplier: Double = TransportConfig.nostrRelayBackoffMultiplier
-    private let maxReconnectAttempts = 10                  // Stop after 10 attempts
+    private let maxReconnectAttempts = TransportConfig.nostrRelayMaxReconnectAttempts
     
     // Reconnection timer
     private var reconnectionTimer: Timer?
@@ -289,7 +289,7 @@ class NostrRelayManager: ObservableObject {
                         
                         // Only log non-gift-wrap events to reduce noise
                         if event.kind != 1059 {
-                            SecureLogger.log("📥 Received Nostr event (kind: \(event.kind)) from relay: \(relayUrl)", 
+                            SecureLogger.log("📥 Event kind=\(event.kind) id=\(event.id.prefix(16))… relay=\(relayUrl)",
                                             category: SecureLogger.session, level: .debug)
                         }
                         
@@ -321,11 +321,11 @@ class NostrRelayManager: ObservableObject {
                         let reason = array.count >= 4 ? (array[3] as? String ?? "no reason given") : "no reason given"
                         if success {
                             _ = Self.pendingGiftWrapIDs.remove(eventId)
-                            SecureLogger.log("✅ Event accepted id=\(eventId.prefix(16))... by relay: \(relayUrl)",
+                            SecureLogger.log("✅ Accepted id=\(eventId.prefix(16))… relay=\(relayUrl)",
                                             category: SecureLogger.session, level: .debug)
                         } else {
                             let isGiftWrap = Self.pendingGiftWrapIDs.remove(eventId) != nil
-                            SecureLogger.log("📮 Event \(eventId.prefix(16))... rejected by relay: \(reason)", 
+                            SecureLogger.log("📮 Rejected id=\(eventId.prefix(16))… reason=\(reason)", 
                                             category: SecureLogger.session, level: isGiftWrap ? .warning : .error)
                         }
                     }
@@ -353,7 +353,7 @@ class NostrRelayManager: ObservableObject {
             let data = try encoder.encode(req)
             let message = String(data: data, encoding: .utf8) ?? ""
             
-            SecureLogger.log("📤 Sending Nostr event (kind: \(event.kind)) to relay: \(relayUrl)", 
+            SecureLogger.log("📤 Send kind=\(event.kind) id=\(event.id.prefix(16))… relay=\(relayUrl)", 
                             category: SecureLogger.session, level: .debug)
             
             connection.send(.string(message)) { [weak self] error in
@@ -568,7 +568,7 @@ struct NostrFilter: Encodable {
         filter.kinds = [1059] // Gift wrap kind
         filter.since = since?.timeIntervalSince1970.toInt()
         filter.tagFilters = ["p": [pubkey]]
-        filter.limit = 100 // Add a reasonable limit
+        filter.limit = TransportConfig.nostrRelayDefaultFetchLimit // reasonable limit
         return filter
     }
 

bitchat/Services/BLEService.swift

@@ -22,12 +22,12 @@ final class BLEService: NSObject {
     static let characteristicUUID = CBUUID(string: "A1B2C3D4-E5F6-4A5B-8C9D-0E1F2A3B4C5D")
     
     // Default per-fragment chunk size when link limits are unknown
-    private let defaultFragmentSize = 469 // ~512 MTU minus protocol overhead
+    private let defaultFragmentSize = TransportConfig.bleDefaultFragmentSize
-    private let maxMessageLength = 10_000
+    private let maxMessageLength = InputValidator.Limits.maxMessageLength
-    private let messageTTL: UInt8 = 7
+    private let messageTTL: UInt8 = TransportConfig.messageTTLDefault
     // Flood/battery controls
-    private let maxInFlightAssemblies = 128 // cap concurrent fragment assemblies
+    private let maxInFlightAssemblies = TransportConfig.bleMaxInFlightAssemblies // cap concurrent fragment assemblies
-    private let highDegreeThreshold = 6 // for adaptive TTL/probabilistic relays
+    private let highDegreeThreshold = TransportConfig.bleHighDegreeThreshold // for adaptive TTL/probabilistic relays
     
     // MARK: - Core State (5 Essential Collections)
     
@@ -70,7 +70,7 @@ final class BLEService: NSObject {
     
     // Simple announce throttling
     private var lastAnnounceSent = Date.distantPast
-    private let announceMinInterval: TimeInterval = 1.0
+    private let announceMinInterval: TimeInterval = TransportConfig.bleAnnounceMinInterval
     
     // Application state tracking (thread-safe)
     #if os(iOS)
@@ -129,8 +129,8 @@ final class BLEService: NSObject {
     private var maintenanceCounter = 0  // Track maintenance cycles
 
     // MARK: - Connection budget & scheduling (central role)
-    private let maxCentralLinks = 6
+    private let maxCentralLinks = TransportConfig.bleMaxCentralLinks
-    private let connectRateLimitInterval: TimeInterval = 0.5
+    private let connectRateLimitInterval: TimeInterval = TransportConfig.bleConnectRateLimitInterval
     private var lastGlobalConnectAttempt: Date = .distantPast
     private struct ConnectionCandidate {
         let peripheral: CBPeripheral
@@ -142,13 +142,13 @@ final class BLEService: NSObject {
     private var connectionCandidates: [ConnectionCandidate] = []
     private var failureCounts: [String: Int] = [:] // Peripheral UUID -> failures
     private var lastIsolatedAt: Date? = nil
-    private var dynamicRSSIThreshold: Int = -90
+    private var dynamicRSSIThreshold: Int = TransportConfig.bleDynamicRSSIThresholdDefault
 
     // MARK: - Adaptive scanning duty-cycle
     private var scanDutyTimer: DispatchSourceTimer?
     private var dutyEnabled: Bool = true
-    private var dutyOnDuration: TimeInterval = 5
+    private var dutyOnDuration: TimeInterval = TransportConfig.bleDutyOnDuration
-    private var dutyOffDuration: TimeInterval = 10
+    private var dutyOffDuration: TimeInterval = TransportConfig.bleDutyOffDuration
     private var dutyActive: Bool = false
 
     // MARK: - Link capability snapshots (thread-safe via bleQueue)
@@ -257,20 +257,15 @@ final class BLEService: NSObject {
 
     func currentPeerSnapshots() -> [TransportPeerSnapshot] {
         collectionsQueue.sync {
-            // Compute nickname collision counts for connected peers
+            let snapshot = Array(peers.values)
-            let connected = peers.values.filter { $0.isConnected }
+            let resolvedNames = PeerDisplayNameResolver.resolve(
-            var counts: [String: Int] = [:]
+                snapshot.map { ($0.id, $0.nickname, $0.isConnected) },
-            for p in connected { counts[p.nickname, default: 0] += 1 }
+                selfNickname: myNickname
-            // Include our own nickname in collision counts so remote matching ours gets suffixed
+            )
-            counts[myNickname, default: 0] += 1
+            return snapshot.map { info in
-            return peers.values.map { info in
+                TransportPeerSnapshot(
-                var display = info.nickname
-                if info.isConnected, (counts[info.nickname] ?? 0) > 1 {
-                    display += "#" + String(info.id.prefix(4))
-                }
-                return TransportPeerSnapshot(
                     id: info.id,
-                    nickname: display,
+                    nickname: resolvedNames[info.id] ?? info.nickname,
                     isConnected: info.isConnected,
                     noisePublicKey: info.noisePublicKey,
                     lastSeen: info.lastSeen
@@ -351,7 +346,9 @@ final class BLEService: NSObject {
         
         // Single maintenance timer for all periodic tasks (dispatch-based for determinism)
         let timer = DispatchSource.makeTimerSource(queue: bleQueue)
-        timer.schedule(deadline: .now() + 10.0, repeating: 10.0, leeway: .seconds(1))
+        timer.schedule(deadline: .now() + TransportConfig.bleMaintenanceInterval,
+                       repeating: TransportConfig.bleMaintenanceInterval,
+                       leeway: .seconds(TransportConfig.bleMaintenanceLeewaySeconds))
         timer.setEventHandler { [weak self] in
             self?.performMaintenance()
         }
@@ -433,7 +430,7 @@ final class BLEService: NSObject {
         
         // Send initial announce after services are ready
         // Use longer delay to avoid conflicts with other announces
-        messageQueue.asyncAfter(deadline: .now() + 2.0) { [weak self] in
+        messageQueue.asyncAfter(deadline: .now() + TransportConfig.bleInitialAnnounceDelaySeconds) { [weak self] in
             self?.sendAnnounce(forceSend: true)
         }
     }
@@ -472,7 +469,7 @@ final class BLEService: NSObject {
         }
         
         // Give leave message a moment to send
-        Thread.sleep(forTimeInterval: 0.05)
+        Thread.sleep(forTimeInterval: TransportConfig.bleThreadSleepWriteShortDelaySeconds)
         
         // Clear pending notifications
         collectionsQueue.sync(flags: .barrier) {
@@ -514,22 +511,9 @@ final class BLEService: NSObject {
 
     func getPeerNicknames() -> [String: String] {
         return collectionsQueue.sync {
-            // Only connected peers
             let connected = peers.filter { $0.value.isConnected }
-            // Count collisions by nickname (include our own nickname)
+            let tuples = connected.map { ($0.key, $0.value.nickname, true) }
-            var counts: [String: Int] = [:]
+            return PeerDisplayNameResolver.resolve(tuples, selfNickname: myNickname)
-            for (_, info) in connected { counts[info.nickname, default: 0] += 1 }
-            counts[myNickname, default: 0] += 1
-            // Build map with suffix for collisions
-            var result: [String: String] = [:]
-            for (id, info) in connected {
-                var name = info.nickname
-                if (counts[info.nickname] ?? 0) > 1 {
-                    name += "#" + String(id.prefix(4))
-                }
-                result[id] = name
-            }
-            return result
         }
     }
     
@@ -981,7 +965,7 @@ final class BLEService: NSObject {
                 if success { sentEncrypted = true; break }
                 collectionsQueue.async(flags: .barrier) { [weak self] in
                     guard let self = self else { return }
-                    if self.pendingNotifications.count < 20 {
+                    if self.pendingNotifications.count < TransportConfig.blePendingNotificationsCapCount {
                         self.pendingNotifications.append((data: data, centrals: [central]))
                         SecureLogger.log("📋 Queued encrypted packet for retry (notification queue full)", category: SecureLogger.session, level: .debug)
                     }
@@ -1112,7 +1096,7 @@ final class BLEService: NSObject {
                 guard let self = self, let c = self.centralManager, c.state == .poweredOn else { return }
                 if c.isScanning { c.stopScan() }
                 // Resume scanning after we expect last fragment to be sent
-                let expectedMs = min(2000, totalFragments * 8) // ~8ms per fragment
+            let expectedMs = min(TransportConfig.bleExpectedWriteMaxMs, totalFragments * TransportConfig.bleExpectedWritePerFragmentMs) // ~8ms per fragment
                 self.bleQueue.asyncAfter(deadline: .now() + .milliseconds(expectedMs)) { [weak self] in
                     self?.startScanning()
                 }
@@ -1143,7 +1127,7 @@ final class BLEService: NSObject {
                 ttl: packet.ttl
             )
             // Pace fragments with small jitter to avoid bursts
-            let delayMs = index * 6 // ~6ms spacing per fragment
+            let delayMs = index * TransportConfig.bleFragmentSpacingMs // ~6ms spacing per fragment
             messageQueue.asyncAfter(deadline: .now() + .milliseconds(delayMs)) { [weak self] in
                 self?.broadcastPacket(fragmentPacket)
             }
@@ -1255,10 +1239,10 @@ final class BLEService: NSObject {
             guard let self = self else { return }
             let now = Date()
             self.recentPacketTimestamps.append(now)
-            // keep last 100 timestamps within 30s window
+            // keep last N timestamps within window
-            let cutoff = now.addingTimeInterval(-30)
+            let cutoff = now.addingTimeInterval(-TransportConfig.bleRecentPacketWindowSeconds)
-            if self.recentPacketTimestamps.count > 100 {
+            if self.recentPacketTimestamps.count > TransportConfig.bleRecentPacketWindowMaxCount {
-                self.recentPacketTimestamps.removeFirst(self.recentPacketTimestamps.count - 100)
+                self.recentPacketTimestamps.removeFirst(self.recentPacketTimestamps.count - TransportConfig.bleRecentPacketWindowMaxCount)
             }
             self.recentPacketTimestamps.removeAll { $0 < cutoff }
         }
@@ -1622,7 +1606,7 @@ final class BLEService: NSObject {
         let timeSinceLastAnnounce = now.timeIntervalSince(lastAnnounceSent)
         
         // Even forced sends should respect a minimum interval to avoid overwhelming BLE
-        let minInterval = forceSend ? 0.2 : announceMinInterval
+        let minInterval = forceSend ? TransportConfig.bleForceAnnounceMinIntervalSeconds : announceMinInterval
         
         if timeSinceLastAnnounce < minInterval {
             // Skipping announce (rate limited)
@@ -1753,12 +1737,14 @@ final class BLEService: NSObject {
         let connectedCount = collectionsQueue.sync { peers.values.filter { $0.isConnected }.count }
         let elapsed = now.timeIntervalSince(lastAnnounceSent)
         if connectedCount == 0 {
-            // Discovery mode: keep frequent announces (~10s)
+            // Discovery mode: keep frequent announces
-            if elapsed >= 10.0 { sendAnnounce(forceSend: true) }
+            if elapsed >= TransportConfig.bleAnnounceIntervalSeconds { sendAnnounce(forceSend: true) }
         } else {
             // Connected mode: announce less often; much less in dense networks
-            let base = connectedCount >= 6 ? 90.0 : 45.0
+            let base = connectedCount >= TransportConfig.bleHighDegreeThreshold ?
-            let jitter = connectedCount >= 6 ? 20.0 : 7.5
+                TransportConfig.bleConnectedAnnounceBaseSecondsDense : TransportConfig.bleConnectedAnnounceBaseSecondsSparse
+            let jitter = connectedCount >= TransportConfig.bleHighDegreeThreshold ?
+                TransportConfig.bleConnectedAnnounceJitterDense : TransportConfig.bleConnectedAnnounceJitterSparse
             let target = base + Double.random(in: -jitter...jitter)
             if elapsed >= target { sendAnnounce(forceSend: true) }
         }
@@ -1799,7 +1785,7 @@ final class BLEService: NSObject {
         
         collectionsQueue.sync(flags: .barrier) {
             for (peerID, peer) in peers {
-                if peer.isConnected && now.timeIntervalSince(peer.lastSeen) > 20 {
+                if peer.isConnected && now.timeIntervalSince(peer.lastSeen) > TransportConfig.blePeerInactivityTimeoutSeconds {
                     // Check if we still have an active BLE connection to this peer
                     let hasPeripheralConnection = peerToPeripheralUUID[peerID] != nil &&
                                                  peripherals[peerToPeripheralUUID[peerID]!]?.isConnected == true
@@ -1839,9 +1825,9 @@ final class BLEService: NSObject {
         // Clean old processed messages efficiently
         messageDeduplicator.cleanup()
         
-        // Clean old fragments (> 30 seconds old)
+        // Clean old fragments (> configured seconds old)
         collectionsQueue.sync(flags: .barrier) {
-            let cutoff = now.addingTimeInterval(-30)
+            let cutoff = now.addingTimeInterval(-TransportConfig.bleFragmentLifetimeSeconds)
             let oldFragments = fragmentMetadata.filter { $0.value.timestamp < cutoff }.map { $0.key }
             for fragmentID in oldFragments {
                 incomingFragments.removeValue(forKey: fragmentID)
@@ -1849,8 +1835,8 @@ final class BLEService: NSObject {
             }
         }
 
-        // Clean old connection timeout backoff entries (> 2 minutes)
+        // Clean old connection timeout backoff entries (> window)
-        let timeoutCutoff = now.addingTimeInterval(-120)
+        let timeoutCutoff = now.addingTimeInterval(-TransportConfig.bleConnectTimeoutBackoffWindowSeconds)
         recentConnectTimeouts = recentConnectTimeouts.filter { $0.value >= timeoutCutoff }
 
         // Clean up stale scheduled relays that somehow persisted (> 2s)
@@ -1864,10 +1850,10 @@ final class BLEService: NSObject {
             }
         }
 
-        // Clean ingress link records older than 3 seconds
+        // Clean ingress link records older than configured seconds
         collectionsQueue.async(flags: .barrier) { [weak self] in
             guard let self = self else { return }
-            let cutoff = now.addingTimeInterval(-3)
+            let cutoff = now.addingTimeInterval(-TransportConfig.bleIngressRecordLifetimeSeconds)
             if !self.ingressByMessageID.isEmpty {
                 self.ingressByMessageID = self.ingressByMessageID.filter { $0.value.timestamp >= cutoff }
             }
@@ -1891,12 +1877,12 @@ final class BLEService: NSObject {
                 if !central.isScanning { startScanning() }
                 dutyActive = true
                 // Adjust duty cycle under dense networks to save battery
-                if connectedCount >= 6 {
+                if connectedCount >= TransportConfig.bleHighDegreeThreshold {
-                    dutyOnDuration = 3
+                    dutyOnDuration = TransportConfig.bleDutyOnDurationDense
-                    dutyOffDuration = 15
+                    dutyOffDuration = TransportConfig.bleDutyOffDurationDense
                 } else {
-                    dutyOnDuration = 5
+                    dutyOnDuration = TransportConfig.bleDutyOnDuration
-                    dutyOffDuration = 10
+                    dutyOffDuration = TransportConfig.bleDutyOffDuration
                 }
                 t.schedule(deadline: .now() + dutyOnDuration, repeating: dutyOnDuration + dutyOffDuration)
                 t.setEventHandler { [weak self] in
@@ -1930,25 +1916,25 @@ final class BLEService: NSObject {
             if lastIsolatedAt == nil { lastIsolatedAt = Date() }
             let iso = lastIsolatedAt ?? Date()
             let elapsed = Date().timeIntervalSince(iso)
-            if elapsed > 60 {
+            if elapsed > TransportConfig.bleIsolationRelaxThresholdSeconds {
-                dynamicRSSIThreshold = -92
+                dynamicRSSIThreshold = TransportConfig.bleRSSIIsolatedRelaxed
             } else {
-                dynamicRSSIThreshold = -90
+                dynamicRSSIThreshold = TransportConfig.bleRSSIIsolatedBase
             }
             return
         }
         lastIsolatedAt = nil
         // Base threshold when connected
-        var threshold = -90
+        var threshold = TransportConfig.bleDynamicRSSIThresholdDefault
         // If we're at budget or queue is large, prefer closer peers
         let linkCount = peripherals.values.filter { $0.isConnected || $0.isConnecting }.count
-        if linkCount >= maxCentralLinks || connectionCandidates.count > 20 {
+        if linkCount >= maxCentralLinks || connectionCandidates.count > TransportConfig.bleConnectionCandidatesMax {
-            threshold = -85
+            threshold = TransportConfig.bleRSSIConnectedThreshold
         }
         // If we have many recent timeouts, raise further
-        let recentTimeouts = recentConnectTimeouts.filter { Date().timeIntervalSince($0.value) < 60 }.count
+        let recentTimeouts = recentConnectTimeouts.filter { Date().timeIntervalSince($0.value) < TransportConfig.bleRecentTimeoutWindowSeconds }.count
-        if recentTimeouts >= 3 {
+        if recentTimeouts >= TransportConfig.bleRecentTimeoutCountThreshold {
-            threshold = max(threshold, -80)
+            threshold = max(threshold, TransportConfig.bleRSSIHighTimeoutThreshold)
         }
         dynamicRSSIThreshold = threshold
     }
@@ -2002,7 +1988,9 @@ extension BLEService: CBCentralManagerDelegate {
                 if a.rssi != b.rssi { return a.rssi > b.rssi }
                 return a.discoveredAt < b.discoveredAt
             }
-            if connectionCandidates.count > 100 { connectionCandidates.removeLast(connectionCandidates.count - 100) }
+            if connectionCandidates.count > TransportConfig.bleConnectionCandidatesMax {
+                connectionCandidates.removeLast(connectionCandidates.count - TransportConfig.bleConnectionCandidatesMax)
+            }
             return
         }
         
@@ -2016,7 +2004,9 @@ extension BLEService: CBCentralManagerDelegate {
                 if a.rssi != b.rssi { return a.rssi > b.rssi }
                 return a.discoveredAt < b.discoveredAt
             }
-            if connectionCandidates.count > 100 { connectionCandidates.removeLast(connectionCandidates.count - 100) }
+            if connectionCandidates.count > TransportConfig.bleConnectionCandidatesMax {
+                connectionCandidates.removeLast(connectionCandidates.count - TransportConfig.bleConnectionCandidatesMax)
+            }
             return
         }
 
@@ -2093,7 +2083,7 @@ extension BLEService: CBCentralManagerDelegate {
         
         // Set a timeout for the connection attempt (slightly longer for reliability)
         // Use BLE queue to mutate BLE-related state consistently
-        bleQueue.asyncAfter(deadline: .now() + 8.0) { [weak self] in
+        bleQueue.asyncAfter(deadline: .now() + TransportConfig.bleConnectTimeoutSeconds) { [weak self] in
             guard let self = self,
                   let state = self.peripherals[peripheralID],
                   state.isConnecting && !state.isConnected else { return }
@@ -2165,7 +2155,7 @@ func centralManager(_ central: CBCentralManager, didConnect peripheral: CBPeriph
         if centralManager?.state == .poweredOn {
             // Stop and restart scanning to ensure we get fresh discovery events
             centralManager?.stopScan()
-            bleQueue.asyncAfter(deadline: .now() + 0.1) { [weak self] in
+            bleQueue.asyncAfter(deadline: .now() + TransportConfig.bleRestartScanDelaySeconds) { [weak self] in
                 self?.startScanning()
             }
         }
@@ -2363,7 +2353,7 @@ extension BLEService: CBPeripheralDelegate {
             SecureLogger.log("🔔 Subscribed to notifications from \(peripheral.name ?? "Unknown")", category: SecureLogger.session, level: .debug)
             
             // Send announce after subscription is confirmed (force send for new connection)
-            messageQueue.asyncAfter(deadline: .now() + 0.1) { [weak self] in
+            messageQueue.asyncAfter(deadline: .now() + TransportConfig.blePostSubscribeAnnounceDelaySeconds) { [weak self] in
                 self?.sendAnnounce(forceSend: true)
             }
         } else {
@@ -2386,7 +2376,9 @@ extension BLEService: CBPeripheralDelegate {
         
         // Process directly on main thread to avoid deadlocks (matches original implementation)
         guard let packet = BinaryProtocol.decode(data) else {
-            SecureLogger.log("❌ Failed to decode notification packet, full data: \(data.map { String(format: "%02x", $0) }.joined(separator: " "))",
+            // Avoid dumping entire payload; log size and short prefix for diagnostics
+            let prefix = data.prefix(16).map { String(format: "%02x", $0) }.joined(separator: " ")
+            SecureLogger.log("❌ Failed to decode notification packet (len=\(data.count), prefix=\(prefix))",
                             category: SecureLogger.session, level: .error)
             return
         }
@@ -2523,7 +2515,7 @@ extension BLEService: CBPeripheralManagerDelegate {
         SecureLogger.log("📥 Central subscribed: \(central.identifier.uuidString)", category: SecureLogger.session, level: .debug)
         subscribedCentrals.append(central)
         // Send announce to the newly subscribed central after a small delay to avoid overwhelming
-        messageQueue.asyncAfter(deadline: .now() + 0.4) { [weak self] in
+        messageQueue.asyncAfter(deadline: .now() + TransportConfig.blePostAnnounceDelaySeconds) { [weak self] in
             self?.sendAnnounce(forceSend: true)
         }
     }
@@ -2682,13 +2674,14 @@ extension BLEService: CBPeripheralManagerDelegate {
                 }
             } else {
                 // If buffer grows suspiciously large, reset to avoid memory leak
-                if combined.count > 1_000_000 { // 1MB cap for safety
+                if combined.count > TransportConfig.blePendingWriteBufferCapBytes { // cap for safety
                     pendingWriteBuffers.removeValue(forKey: centralUUID)
                     SecureLogger.log("⚠️ Dropping oversized pending write buffer (\(combined.count) bytes) for central \(centralUUID)", category: SecureLogger.session, level: .warning)
                 }
                 // If this was a single short write and still failed, log the raw chunk for debugging
                 if !hasMultiple, let only = sorted.first, let raw = only.value {
-                    SecureLogger.log("❌ Failed to decode packet from central, full data: \(raw.map { String(format: "%02x", $0) }.joined(separator: " "))", category: SecureLogger.session, level: .error)
+                    let prefix = raw.prefix(16).map { String(format: "%02x", $0) }.joined(separator: " ")
+                    SecureLogger.log("❌ Failed to decode packet from central (len=\(raw.count), prefix=\(prefix))", category: SecureLogger.session, level: .error)
                 }
             }
         }

bitchat/Services/LocationChannelManager.swift

@@ -39,7 +39,7 @@ final class LocationChannelManager: NSObject, CLLocationManagerDelegate, Observa
         super.init()
         cl.delegate = self
         cl.desiredAccuracy = kCLLocationAccuracyHundredMeters
-        cl.distanceFilter = 1000 // meters; we're not tracking continuously
+        cl.distanceFilter = TransportConfig.locationDistanceFilterMeters // meters; we're not tracking continuously
         // Load selection
         if let data = UserDefaults.standard.data(forKey: userDefaultsKey),
            let channel = try? JSONDecoder().decode(ChannelID.self, from: data) {
@@ -93,7 +93,7 @@ final class LocationChannelManager: NSObject, CLLocationManagerDelegate, Observa
     }
 
     /// Begin periodic one-shot location refreshes while a selector UI is visible.
-    func beginLiveRefresh(interval: TimeInterval = 5.0) {
+    func beginLiveRefresh(interval: TimeInterval = TransportConfig.locationLiveRefreshInterval) {
         guard permissionState == .authorized else { return }
         // Switch to a lightweight periodic one-shot request (polling) while the sheet is open
         refreshTimer?.invalidate()

bitchat/Services/NostrTransport.swift

@@ -20,7 +20,7 @@ final class NostrTransport: Transport {
     }
     private var readQueue: [QueuedRead] = []
     private var isSendingReadAcks = false
-    private let readAckInterval: TimeInterval = 0.35 // ~3 per second
+    private let readAckInterval: TimeInterval = TransportConfig.nostrReadAckInterval
 
     var myPeerID: String { senderPeerID }
     var myNickname: String { "" }
@@ -48,16 +48,7 @@ final class NostrTransport: Transport {
 
     func sendPrivateMessage(_ content: String, to peerID: String, recipientNickname: String, messageID: String) {
         Task { @MainActor in
-            // Resolve favorite by full noise key or by short peerID fallback
+            guard let recipientNpub = resolveRecipientNpub(for: peerID) else { return }
-            var recipientNostrPubkey: String?
-            if let noiseKey = Data(hexString: peerID),
-               let fav = FavoritesPersistenceService.shared.getFavoriteStatus(for: noiseKey) {
-                recipientNostrPubkey = fav.peerNostrPublicKey
-            }
-            if recipientNostrPubkey == nil, peerID.count == 16 {
-                recipientNostrPubkey = FavoritesPersistenceService.shared.getFavoriteStatus(forPeerID: peerID)?.peerNostrPublicKey
-            }
-            guard let recipientNpub = recipientNostrPubkey else { return }
             guard let senderIdentity = try? NostrIdentityBridge.getCurrentNostrIdentity() else { return }
             SecureLogger.log("NostrTransport: preparing PM to \(recipientNpub.prefix(16))… for peerID \(peerID.prefix(8))… id=\(messageID.prefix(8))…",
                             category: SecureLogger.session, level: .debug)
@@ -105,15 +96,7 @@ final class NostrTransport: Transport {
         guard !readQueue.isEmpty else { isSendingReadAcks = false; return }
         let item = readQueue.removeFirst()
         Task { @MainActor in
-            var recipientNostrPubkey: String?
+            guard let recipientNpub = resolveRecipientNpub(for: item.peerID) else { scheduleNextReadAck(); return }
-            if let noiseKey = Data(hexString: item.peerID),
-               let fav = FavoritesPersistenceService.shared.getFavoriteStatus(for: noiseKey) {
-                recipientNostrPubkey = fav.peerNostrPublicKey
-            }
-            if recipientNostrPubkey == nil, item.peerID.count == 16 {
-                recipientNostrPubkey = FavoritesPersistenceService.shared.getFavoriteStatus(forPeerID: item.peerID)?.peerNostrPublicKey
-            }
-            guard let recipientNpub = recipientNostrPubkey else { scheduleNextReadAck(); return }
             guard let senderIdentity = try? NostrIdentityBridge.getCurrentNostrIdentity() else { scheduleNextReadAck(); return }
             SecureLogger.log("NostrTransport: preparing READ ack for id=\(item.receipt.originalMessageID.prefix(8))… to \(recipientNpub.prefix(16))…",
                             category: SecureLogger.session, level: .debug)
@@ -149,15 +132,7 @@ final class NostrTransport: Transport {
 
     func sendFavoriteNotification(to peerID: String, isFavorite: Bool) {
         Task { @MainActor in
-            var recipientNostrPubkey: String?
+            guard let recipientNpub = resolveRecipientNpub(for: peerID) else { return }
-            if let noiseKey = Data(hexString: peerID),
-               let fav = FavoritesPersistenceService.shared.getFavoriteStatus(for: noiseKey) {
-                recipientNostrPubkey = fav.peerNostrPublicKey
-            }
-            if recipientNostrPubkey == nil, peerID.count == 16 {
-                recipientNostrPubkey = FavoritesPersistenceService.shared.getFavoriteStatus(forPeerID: peerID)?.peerNostrPublicKey
-            }
-            guard let recipientNpub = recipientNostrPubkey else { return }
             guard let senderIdentity = try? NostrIdentityBridge.getCurrentNostrIdentity() else { return }
             let content = isFavorite ? "[FAVORITED]:\(senderIdentity.npub)" : "[UNFAVORITED]:\(senderIdentity.npub)"
             SecureLogger.log("NostrTransport: preparing FAVORITE(\(isFavorite)) to \(recipientNpub.prefix(16))…",
@@ -183,18 +158,26 @@ final class NostrTransport: Transport {
         }
     }
 
+    // MARK: - Helpers
+    @MainActor
+    private func resolveRecipientNpub(for peerID: String) -> String? {
+        if let noiseKey = Data(hexString: peerID),
+           let fav = FavoritesPersistenceService.shared.getFavoriteStatus(for: noiseKey),
+           let npub = fav.peerNostrPublicKey {
+            return npub
+        }
+        if peerID.count == 16,
+           let fav = FavoritesPersistenceService.shared.getFavoriteStatus(forPeerID: peerID),
+           let npub = fav.peerNostrPublicKey {
+            return npub
+        }
+        return nil
+    }
+
     func sendBroadcastAnnounce() { /* no-op for Nostr */ }
     func sendDeliveryAck(for messageID: String, to peerID: String) {
         Task { @MainActor in
-            var recipientNostrPubkey: String?
+            guard let recipientNpub = resolveRecipientNpub(for: peerID) else { return }
-            if let noiseKey = Data(hexString: peerID),
-               let fav = FavoritesPersistenceService.shared.getFavoriteStatus(for: noiseKey) {
-                recipientNostrPubkey = fav.peerNostrPublicKey
-            }
-            if recipientNostrPubkey == nil, peerID.count == 16 {
-                recipientNostrPubkey = FavoritesPersistenceService.shared.getFavoriteStatus(forPeerID: peerID)?.peerNostrPublicKey
-            }
-            guard let recipientNpub = recipientNostrPubkey else { return }
             guard let senderIdentity = try? NostrIdentityBridge.getCurrentNostrIdentity() else { return }
             SecureLogger.log("NostrTransport: preparing DELIVERED ack for id=\(messageID.prefix(8))… to \(recipientNpub.prefix(16))…",
                             category: SecureLogger.session, level: .debug)

bitchat/Services/PrivateChatManager.swift

@@ -27,7 +27,7 @@ class PrivateChatManager: ObservableObject {
     }
 
     // Cap for messages stored per private chat
-    private let privateChatCap = 1337
+    private let privateChatCap = TransportConfig.privateChatCap
     
     /// Start a private chat with a peer
     func startChat(with peerID: String) {

bitchat/Services/Transport.swift

@@ -3,7 +3,7 @@ import Combine
 
 /// Abstract transport interface used by ChatViewModel and services.
 /// BLEService implements this protocol; a future Nostr transport can too.
-struct TransportPeerSnapshot {
+struct TransportPeerSnapshot: Equatable, Hashable {
     let id: String
     let nickname: String
     let isConnected: Bool

bitchat/Services/TransportConfig.swift

@@ -0,0 +1,161 @@
+import Foundation
+
+/// Centralized knobs for transport- and UI-related limits.
+/// Keep values aligned with existing behavior when replacing magic numbers.
+enum TransportConfig {
+    // BLE / Protocol
+    static let bleDefaultFragmentSize: Int = 469            // ~512 MTU minus protocol overhead
+    static let messageTTLDefault: UInt8 = 7                 // Default TTL for mesh flooding
+    static let bleMaxInFlightAssemblies: Int = 128          // Cap concurrent fragment assemblies
+    static let bleHighDegreeThreshold: Int = 6              // For adaptive TTL/probabilistic relays
+
+    // UI / Storage Caps
+    static let privateChatCap: Int = 1337
+    static let meshTimelineCap: Int = 1337
+    static let geoTimelineCap: Int = 1337
+    static let contentLRUCap: Int = 2000
+
+    // Timers
+    static let networkResetGraceSeconds: TimeInterval = 600 // 10 minutes
+    static let basePublicFlushInterval: TimeInterval = 0.08  // ~12.5 fps batching
+
+    // BLE duty/announce/connect
+    static let bleConnectRateLimitInterval: TimeInterval = 0.5
+    static let bleMaxCentralLinks: Int = 6
+    static let bleDutyOnDuration: TimeInterval = 5.0
+    static let bleDutyOffDuration: TimeInterval = 10.0
+    static let bleAnnounceMinInterval: TimeInterval = 1.0
+
+    // BLE discovery/quality thresholds
+    static let bleDynamicRSSIThresholdDefault: Int = -90
+    static let bleConnectionCandidatesMax: Int = 100
+    static let blePendingWriteBufferCapBytes: Int = 1_000_000
+    static let blePendingNotificationsCapCount: Int = 20
+
+    // Nostr
+    static let nostrReadAckInterval: TimeInterval = 0.35 // ~3 per second
+
+    // UI thresholds
+    static let uiLateInsertThreshold: TimeInterval = 15.0
+    static let uiProcessedNostrEventsCap: Int = 2000
+    static let uiChannelInactivityThresholdSeconds: TimeInterval = 9 * 60
+    
+    // UI rate limiters (token buckets)
+    static let uiSenderRateBucketCapacity: Double = 5
+    static let uiSenderRateBucketRefillPerSec: Double = 1.0
+    static let uiContentRateBucketCapacity: Double = 3
+    static let uiContentRateBucketRefillPerSec: Double = 0.5
+
+    // UI sleeps/delays
+    static let uiStartupInitialDelaySeconds: TimeInterval = 1.0
+    static let uiStartupShortSleepNs: UInt64 = 200_000_000
+    static let uiStartupPhaseDurationSeconds: TimeInterval = 2.0
+    static let uiAsyncShortSleepNs: UInt64 = 100_000_000
+    static let uiAsyncMediumSleepNs: UInt64 = 500_000_000
+    static let uiReadReceiptRetryShortSeconds: TimeInterval = 0.1
+    static let uiReadReceiptRetryLongSeconds: TimeInterval = 0.5
+    static let uiBatchDispatchStaggerSeconds: TimeInterval = 0.15
+    static let uiScrollThrottleSeconds: TimeInterval = 0.5
+    static let uiAnimationShortSeconds: TimeInterval = 0.15
+    static let uiAnimationMediumSeconds: TimeInterval = 0.2
+    static let uiAnimationSidebarSeconds: TimeInterval = 0.25
+    static let uiRecentCutoffFiveMinutesSeconds: TimeInterval = 5 * 60
+
+    // BLE maintenance & thresholds
+    static let bleMaintenanceInterval: TimeInterval = 10.0
+    static let bleMaintenanceLeewaySeconds: Int = 1
+    static let bleIsolationRelaxThresholdSeconds: TimeInterval = 60
+    static let bleRecentTimeoutWindowSeconds: TimeInterval = 60
+    static let bleRecentTimeoutCountThreshold: Int = 3
+    static let bleRSSIIsolatedBase: Int = -90
+    static let bleRSSIIsolatedRelaxed: Int = -92
+    static let bleRSSIConnectedThreshold: Int = -85
+    static let bleRSSIHighTimeoutThreshold: Int = -80
+    static let blePeerInactivityTimeoutSeconds: TimeInterval = 20.0
+    static let bleFragmentLifetimeSeconds: TimeInterval = 30.0
+    static let bleIngressRecordLifetimeSeconds: TimeInterval = 3.0
+    static let bleConnectTimeoutBackoffWindowSeconds: TimeInterval = 120.0
+    static let bleRecentPacketWindowSeconds: TimeInterval = 30.0
+    static let bleRecentPacketWindowMaxCount: Int = 100
+    static let bleThreadSleepWriteShortDelaySeconds: TimeInterval = 0.05
+    static let bleExpectedWritePerFragmentMs: Int = 8
+    static let bleExpectedWriteMaxMs: Int = 2000
+    static let bleFragmentSpacingMs: Int = 6
+    static let bleAnnounceIntervalSeconds: TimeInterval = 10.0
+    static let bleDutyOnDurationDense: TimeInterval = 3.0
+    static let bleDutyOffDurationDense: TimeInterval = 15.0
+    static let bleConnectedAnnounceBaseSecondsDense: TimeInterval = 90.0
+    static let bleConnectedAnnounceBaseSecondsSparse: TimeInterval = 45.0
+    static let bleConnectedAnnounceJitterDense: TimeInterval = 20.0
+    static let bleConnectedAnnounceJitterSparse: TimeInterval = 7.5
+
+    // Location
+    static let locationDistanceFilterMeters: Double = 1000
+    static let locationLiveRefreshInterval: TimeInterval = 5.0
+
+    // Nostr geohash
+    static let nostrGeohashInitialLookbackSeconds: TimeInterval = 3600
+    static let nostrGeohashInitialLimit: Int = 200
+    static let nostrGeoRelayCount: Int = 5
+    static let nostrGeohashSampleLookbackSeconds: TimeInterval = 300
+    static let nostrGeohashSampleLimit: Int = 100
+    static let nostrDMSubscribeLookbackSeconds: TimeInterval = 86400
+
+    // Nostr helpers
+    static let nostrShortKeyDisplayLength: Int = 8
+    static let nostrConvKeyPrefixLength: Int = 16
+
+    // Compression
+    static let compressionThresholdBytes: Int = 100
+
+    // Message deduplication
+    static let messageDedupMaxAgeSeconds: TimeInterval = 300
+    static let messageDedupMaxCount: Int = 1000
+
+    // Verification QR
+    static let verificationQRMaxAgeSeconds: TimeInterval = 5 * 60
+
+    // Nostr relay backoff
+    static let nostrRelayInitialBackoffSeconds: TimeInterval = 1.0
+    static let nostrRelayMaxBackoffSeconds: TimeInterval = 300.0
+    static let nostrRelayBackoffMultiplier: Double = 2.0
+    static let nostrRelayMaxReconnectAttempts: Int = 10
+    static let nostrRelayDefaultFetchLimit: Int = 100
+
+    // Geo relay directory
+    static let geoRelayFetchIntervalSeconds: TimeInterval = 60 * 60 * 24
+
+    // BLE operational delays
+    static let bleInitialAnnounceDelaySeconds: TimeInterval = 2.0
+    static let bleConnectTimeoutSeconds: TimeInterval = 8.0
+    static let bleRestartScanDelaySeconds: TimeInterval = 0.1
+    static let blePostSubscribeAnnounceDelaySeconds: TimeInterval = 0.1
+    static let blePostAnnounceDelaySeconds: TimeInterval = 0.4
+    static let bleForceAnnounceMinIntervalSeconds: TimeInterval = 0.2
+
+    // Content hashing / formatting
+    static let contentKeyPrefixLength: Int = 256
+    static let uiLongMessageLengthThreshold: Int = 2000
+    static let uiVeryLongTokenThreshold: Int = 512
+    static let uiLongMessageLineLimit: Int = 30
+    static let uiFingerprintSampleCount: Int = 3
+    
+    // UI swipe/gesture thresholds
+    static let uiBackSwipeTranslationLarge: CGFloat = 50
+    static let uiBackSwipeTranslationSmall: CGFloat = 30
+    static let uiBackSwipeVelocityThreshold: CGFloat = 300
+    
+    // UI color tuning
+    static let uiColorHueAvoidanceDelta: Double = 0.05
+    static let uiColorHueOffset: Double = 0.12
+
+    // UI windowing (infinite scroll)
+    static let uiWindowInitialCountPublic: Int = 300
+    static let uiWindowInitialCountPrivate: Int = 300
+    static let uiWindowStepCount: Int = 200
+
+    // Share extension
+    static let uiShareExtensionDismissDelaySeconds: TimeInterval = 0.3
+    static let uiShareAcceptWindowSeconds: TimeInterval = 30.0
+    static let uiMigrationCutoffSeconds: TimeInterval = 24 * 60 * 60
+}

bitchat/Services/VerificationService.swift

@@ -102,7 +102,7 @@ final class VerificationService {
     }
 
     /// Verify a scanned QR and return the parsed payload if valid (signature + freshness checks)
-    func verifyScannedQR(_ urlString: String, maxAge: TimeInterval = 5 * 60) -> VerificationQR? {
+    func verifyScannedQR(_ urlString: String, maxAge: TimeInterval = TransportConfig.verificationQRMaxAgeSeconds) -> VerificationQR? {
         guard let url = URL(string: urlString), let qr = VerificationQR.fromURL(url) else { return nil }
         // Freshness
         let now = Date().timeIntervalSince1970

bitchat/Utils/CompressionUtil.swift

@@ -11,7 +11,7 @@ import Compression
 
 struct CompressionUtil {
     // Compression threshold - don't compress if data is smaller than this
-    static let compressionThreshold = 100 // bytes
+    static let compressionThreshold = TransportConfig.compressionThresholdBytes // bytes
     
     // Compress data using zlib algorithm (most compatible)
     static func compress(_ data: Data) -> Data? {

bitchat/Utils/MessageDeduplicator.swift

@@ -11,8 +11,8 @@ final class MessageDeduplicator {
     private var entries: [Entry] = []
     private var lookup = Set<String>()
     private let lock = NSLock()
-    private let maxAge: TimeInterval = 300  // 5 minutes
+    private let maxAge: TimeInterval = TransportConfig.messageDedupMaxAgeSeconds  // 5 minutes
-    private let maxCount = 1000
+    private let maxCount = TransportConfig.messageDedupMaxCount
 
     /// Check if message is duplicate and add if not
     func isDuplicate(_ messageID: String) -> Bool {
@@ -84,4 +84,3 @@ final class MessageDeduplicator {
         }
     }
 }
-

bitchat/Utils/PeerDisplayNameResolver.swift

@@ -0,0 +1,29 @@
+import Foundation
+
+/// Resolves a stable display name for peers, adding a short suffix when collisions exist.
+struct PeerDisplayNameResolver {
+    /// Computes display names with a `#xxxx` suffix for connected peers when nickname collisions occur.
+    /// - Parameters:
+    ///   - peers: Array of tuples (id, nickname, isConnected).
+    ///   - selfNickname: The local user's current nickname, included in collision counts to suffix remotes matching it.
+    /// - Returns: Map of peerID -> displayName.
+    static func resolve(_ peers: [(id: String, nickname: String, isConnected: Bool)], selfNickname: String) -> [String: String] {
+        // Count collisions among connected peers and include our own nickname
+        var counts: [String: Int] = [:]
+        for p in peers where p.isConnected {
+            counts[p.nickname, default: 0] += 1
+        }
+        counts[selfNickname, default: 0] += 1
+
+        var result: [String: String] = [:]
+        for p in peers {
+            var name = p.nickname
+            if p.isConnected, (counts[p.nickname] ?? 0) > 1 {
+                name += "#" + String(p.id.prefix(4))
+            }
+            result[p.id] = name
+        }
+        return result
+    }
+}
+

bitchat/ViewModels/ChatViewModel.swift

@@ -145,10 +145,10 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
 
     private var rateBucketsBySender: [String: TokenBucket] = [:]
     private var rateBucketsByContent: [String: TokenBucket] = [:]
-    private let senderBucketCapacity: Double = 5
+    private let senderBucketCapacity: Double = TransportConfig.uiSenderRateBucketCapacity
-    private let senderBucketRefill: Double = 1 // tokens per second
+    private let senderBucketRefill: Double = TransportConfig.uiSenderRateBucketRefillPerSec // tokens per second
-    private let contentBucketCapacity: Double = 3
+    private let contentBucketCapacity: Double = TransportConfig.uiContentRateBucketCapacity
-    private let contentBucketRefill: Double = 0.5 // tokens per second
+    private let contentBucketRefill: Double = TransportConfig.uiContentRateBucketRefillPerSec // tokens per second
 
     @MainActor
     private func normalizedSenderKey(for message: BitchatMessage) -> String {
@@ -192,7 +192,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         if last < ns.length { simplified += ns.substring(with: NSRange(location: last, length: ns.length - last)) }
         let trimmed = simplified.trimmingCharacters(in: .whitespacesAndNewlines)
         let collapsed = trimmed.replacingOccurrences(of: "\\s+", with: " ", options: .regularExpression)
-        let prefix = String(collapsed.prefix(256))
+        let prefix = String(collapsed.prefix(TransportConfig.contentKeyPrefixLength))
         // Fast djb2 hash
         let h = djb2(prefix)
         return String(format: "h:%016llx", h)
@@ -201,7 +201,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     // Persistent recent content map (LRU) to speed near-duplicate checks
     private var contentLRUMap: [String: Date] = [:]
     private var contentLRUOrder: [String] = []
-    private let contentLRUCap = 2000
+    private let contentLRUCap = TransportConfig.contentLRUCap
     private func recordContentKey(_ key: String, timestamp: Date) {
         if contentLRUMap[key] == nil { contentLRUOrder.append(key) }
         contentLRUMap[key] = timestamp
@@ -219,13 +219,13 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     
     @Published var messages: [BitchatMessage] = []
     @Published var currentColorScheme: ColorScheme = .light
-    private let maxMessages = 1337 // Maximum messages before oldest are removed
+    private let maxMessages = TransportConfig.meshTimelineCap // Maximum messages before oldest are removed
     @Published var isConnected = false
     private var hasNotifiedNetworkAvailable = false
     private var recentlySeenPeers: Set<String> = []
     private var lastNetworkNotificationTime = Date.distantPast
     private var networkResetTimer: Timer? = nil
-    private let networkResetGraceSeconds: TimeInterval = 600 // 10 minutes; avoid refiring on short drops/reconnects
+    private let networkResetGraceSeconds: TimeInterval = TransportConfig.networkResetGraceSeconds // avoid refiring on short drops/reconnects
     @Published var nickname: String = "" {
         didSet {
             // Trim whitespace whenever nickname is set
@@ -349,7 +349,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     // PeerManager replaced by UnifiedPeerService
     private var processedNostrEvents = Set<String>()  // Simple deduplication
     private var processedNostrEventOrder: [String] = []
-    private let maxProcessedNostrEvents = 2000
+    private let maxProcessedNostrEvents = TransportConfig.uiProcessedNostrEventsCap
     private let userDefaults = UserDefaults.standard
     private let nicknameKey = "bitchat.nickname"
     // Location channel state (macOS supports manual geohash selection)
@@ -386,14 +386,14 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     // Messages are naturally ephemeral - no persistent storage
     // Persist mesh public timeline across channel switches
     private var meshTimeline: [BitchatMessage] = []
-    private let meshTimelineCap = 1337
+    private let meshTimelineCap = TransportConfig.meshTimelineCap
     // Persist per-geohash public timelines across switches
     private var geoTimelines: [String: [BitchatMessage]] = [:] // geohash -> messages
-    private let geoTimelineCap = 1337
+    private let geoTimelineCap = TransportConfig.geoTimelineCap
     // Channel activity tracking for background nudges
     private var lastPublicActivityAt: [String: Date] = [:]   // channelKey -> last activity time
     private var lastPublicActivityNotifyAt: [String: Date] = [:]
-    private let channelInactivityThreshold: TimeInterval = 9 * 60
+    private let channelInactivityThreshold: TimeInterval = TransportConfig.uiChannelInactivityThresholdSeconds
     // Geohash participants (per geohash: pubkey -> lastSeen)
     private var geoParticipants: [String: [String: Date]] = [:]
     @Published private(set) var geohashPeople: [GeoPerson] = []
@@ -428,11 +428,11 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     // Buffer incoming public messages and flush in small batches to reduce UI invalidations
     private var publicBuffer: [BitchatMessage] = []
     private var publicBufferTimer: Timer? = nil
-    private let basePublicFlushInterval: TimeInterval = 0.08 // ~12.5 fps batching
+    private let basePublicFlushInterval: TimeInterval = TransportConfig.basePublicFlushInterval
-    private var dynamicPublicFlushInterval: TimeInterval = 0.08
+    private var dynamicPublicFlushInterval: TimeInterval = TransportConfig.basePublicFlushInterval
     private var recentBatchSizes: [Int] = []
     @Published private(set) var isBatchingPublic: Bool = false
-    private let lateInsertThreshold: TimeInterval = 15.0
+    private let lateInsertThreshold: TimeInterval = TransportConfig.uiLateInsertThreshold
     
     // Track sent read receipts to avoid duplicates (persisted across launches)
     // Note: Persistence happens automatically in didSet, no lifecycle observers needed
@@ -441,21 +441,9 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             // Only persist if there are changes
             guard oldValue != sentReadReceipts else { return }
             
-            // Persist to UserDefaults whenever it changes
+            // Persist to UserDefaults whenever it changes (no manual synchronize/verify re-read)
             if let data = try? JSONEncoder().encode(Array(sentReadReceipts)) {
                 UserDefaults.standard.set(data, forKey: "sentReadReceipts")
-                // Force synchronization for immediate persistence (ensures data is written to disk)
-                UserDefaults.standard.synchronize()
-                
-                // Verify persistence by re-reading
-                if let verifyData = UserDefaults.standard.data(forKey: "sentReadReceipts"),
-                   let _ = try? JSONDecoder().decode([String].self, from: verifyData) {
-                    // Only log errors, not successful persistence
-                    // Successfully persisted
-                } else {
-                    SecureLogger.log("⚠️ Failed to verify persistence of read receipts",
-                                    category: SecureLogger.session, level: .error)
-                }
             } else {
                 SecureLogger.log("❌ Failed to encode read receipts for persistence",
                                 category: SecureLogger.session, level: .error)
@@ -518,7 +506,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         // Log startup info
         
         // Log fingerprint after a delay to ensure encryption service is ready
-        DispatchQueue.main.asyncAfter(deadline: .now() + 1.0) { [weak self] in
+        DispatchQueue.main.asyncAfter(deadline: .now() + TransportConfig.uiStartupInitialDelaySeconds) { [weak self] in
             if let self = self {
                 _ = self.getMyFingerprint()
             }
@@ -538,7 +526,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             
             // Small delay to ensure read receipts are fully loaded
             // This prevents race conditions where messages arrive before initialization completes
-            try? await Task.sleep(nanoseconds: 200_000_000) // 0.2 seconds
+            try? await Task.sleep(nanoseconds: TransportConfig.uiStartupShortSleepNs) // 0.2 seconds
             
             // Set up Nostr message handling directly
             setupNostrMessageHandling()
@@ -551,7 +539,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             // 1. Skip cleanup of read receipts
             // 2. Only block OLD messages from being marked as unread
             Task { @MainActor in
-                try? await Task.sleep(nanoseconds: 2_000_000_000) // 2 seconds
+                try? await Task.sleep(nanoseconds: UInt64(TransportConfig.uiStartupPhaseDurationSeconds * 1_000_000_000)) // 2 seconds
                 self.isStartupPhase = false
             }
             
@@ -703,8 +691,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     // MARK: - Deinitialization
     
     deinit {
-        // Force immediate save
+        // No need to force UserDefaults synchronization
-        userDefaults.synchronize()
     }
     
     // Resubscribe to the active geohash channel without clearing timeline
@@ -720,8 +707,15 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         startGeoParticipantsTimer()
         // Unsubscribe + resubscribe
         NostrRelayManager.shared.unsubscribe(id: subID)
-        let filter = NostrFilter.geohashEphemeral(ch.geohash, since: Date().addingTimeInterval(-3600), limit: 200)
+        let filter = NostrFilter.geohashEphemeral(
-        let subRelays = GeoRelayDirectory.shared.closestRelays(toGeohash: ch.geohash, count: 5)
+            ch.geohash,
+            since: Date().addingTimeInterval(-TransportConfig.nostrGeohashInitialLookbackSeconds),
+            limit: TransportConfig.nostrGeohashInitialLimit
+        )
+        let subRelays = GeoRelayDirectory.shared.closestRelays(
+            toGeohash: ch.geohash,
+            count: TransportConfig.nostrGeoRelayCount
+        )
         NostrRelayManager.shared.subscribe(filter: filter, id: subID, relayUrls: subRelays) { [weak self] event in
             guard let self = self else { return }
             guard event.kind == NostrProtocol.EventKind.ephemeralEvent.rawValue else { return }
@@ -739,9 +733,9 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                 self.geoNicknames[event.pubkey.lowercased()] = nick
             }
             // Store mapping for geohash sender IDs used in messages (ensures consistent colors)
-            let key16 = "nostr_" + String(event.pubkey.prefix(16))
+            let key16 = "nostr_" + String(event.pubkey.prefix(TransportConfig.nostrConvKeyPrefixLength))
             self.nostrKeyMapping[key16] = event.pubkey
-            let key8 = "nostr:" + String(event.pubkey.prefix(8))
+            let key8 = "nostr:" + String(event.pubkey.prefix(TransportConfig.nostrShortKeyDisplayLength))
             self.nostrKeyMapping[key8] = event.pubkey
 
             // Update participants last-seen for this pubkey
@@ -768,7 +762,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                 originalSender: nil,
                 isPrivate: false,
                 recipientNickname: nil,
-                senderPeerID: "nostr:\(event.pubkey.prefix(8))",
+                senderPeerID: "nostr:\(event.pubkey.prefix(TransportConfig.nostrShortKeyDisplayLength))",
                 mentions: mentions.isEmpty ? nil : mentions
             )
             Task { @MainActor in
@@ -783,7 +777,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             let id = try NostrIdentityBridge.deriveIdentity(forGeohash: ch.geohash)
             let dmSub = "geo-dm-\(ch.geohash)"
             geoDmSubscriptionID = dmSub
-            let dmFilter = NostrFilter.giftWrapsFor(pubkey: id.publicKeyHex, since: Date().addingTimeInterval(-86400))
+            let dmFilter = NostrFilter.giftWrapsFor(pubkey: id.publicKeyHex, since: Date().addingTimeInterval(-TransportConfig.nostrDMSubscribeLookbackSeconds))
             NostrRelayManager.shared.subscribe(filter: dmFilter, id: dmSub) { [weak self] giftWrap in
                 guard let self = self else { return }
                 if self.processedNostrEvents.contains(giftWrap.id) { return }
@@ -795,7 +789,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                 guard packet.type == MessageType.noiseEncrypted.rawValue else { return }
                 guard let noisePayload = NoisePayload.decode(packet.payload) else { return }
                 let messageTimestamp = Date(timeIntervalSince1970: TimeInterval(rumorTs))
-                let convKey = "nostr_" + String(senderPubkey.prefix(16))
+                let convKey = "nostr_" + String(senderPubkey.prefix(TransportConfig.nostrConvKeyPrefixLength))
                 self.nostrKeyMapping[convKey] = senderPubkey
                 switch noisePayload.type {
                 case .privateMessage:
@@ -903,7 +897,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     
     func saveNickname() {
         userDefaults.set(nickname, forKey: nicknameKey)
-        userDefaults.synchronize() // Force immediate save
+        // Persist nickname; no need to force synchronize
         
         // Send announce with new nickname to all peers
         meshService.sendBroadcastAnnounce()
@@ -1095,7 +1089,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
            chatFingerprint == fingerprintStr {
             // Send read receipts for any unread messages from this peer
             // Use a small delay to ensure the connection is fully established
-            DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) { [weak self] in
+        DispatchQueue.main.asyncAfter(deadline: .now() + TransportConfig.uiReadReceiptRetryLongSeconds) { [weak self] in
                 self?.markPrivateMessagesAsRead(from: peerID)
             }
         }
@@ -1221,7 +1215,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                let myGeoIdentity = try? NostrIdentityBridge.deriveIdentity(forGeohash: ch.geohash) {
                 let suffix = String(myGeoIdentity.publicKeyHex.suffix(4))
                 displaySender = nickname + "#" + suffix
-                localSenderPeerID = "nostr:\(myGeoIdentity.publicKeyHex.prefix(8))"
+                localSenderPeerID = "nostr:\(myGeoIdentity.publicKeyHex.prefix(TransportConfig.nostrShortKeyDisplayLength))"
             }
 
             let message = BitchatMessage(
@@ -1277,7 +1271,10 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                             nickname: self.nickname,
                             teleported: LocationChannelManager.shared.teleported
                         )
-                        let targetRelays = GeoRelayDirectory.shared.closestRelays(toGeohash: ch.geohash, count: 5)
+                        let targetRelays = GeoRelayDirectory.shared.closestRelays(
+                            toGeohash: ch.geohash,
+                            count: TransportConfig.nostrGeoRelayCount
+                        )
                         if targetRelays.isEmpty {
                             SecureLogger.log("Geo: no geohash relays available for \(ch.geohash); not sending", category: SecureLogger.session, level: .warning)
                         } else {
@@ -1359,7 +1356,11 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         let subID = "geo-\(ch.geohash)"
         geoSubscriptionID = subID
         startGeoParticipantsTimer()
-        let filter = NostrFilter.geohashEphemeral(ch.geohash, since: Date().addingTimeInterval(-3600), limit: 200)
+        let filter = NostrFilter.geohashEphemeral(
+            ch.geohash,
+            since: Date().addingTimeInterval(-TransportConfig.nostrGeohashInitialLookbackSeconds),
+            limit: TransportConfig.nostrGeohashInitialLimit
+        )
         let subRelays = GeoRelayDirectory.shared.closestRelays(toGeohash: ch.geohash, count: 5)
         NostrRelayManager.shared.subscribe(filter: filter, id: subID, relayUrls: subRelays) { [weak self] event in
             guard let self = self else { return }
@@ -1401,9 +1402,9 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                 return
             }
             // Store mapping for geohash DM initiation
-            let key16 = "nostr_" + String(event.pubkey.prefix(16))
+            let key16 = "nostr_" + String(event.pubkey.prefix(TransportConfig.nostrConvKeyPrefixLength))
             self.nostrKeyMapping[key16] = event.pubkey
-            let key8 = "nostr:" + String(event.pubkey.prefix(8))
+            let key8 = "nostr:" + String(event.pubkey.prefix(TransportConfig.nostrShortKeyDisplayLength))
             self.nostrKeyMapping[key8] = event.pubkey
             // Update participants last-seen for this pubkey
             self.recordGeoParticipant(pubkeyHex: event.pubkey)
@@ -1426,7 +1427,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                 originalSender: nil,
                 isPrivate: false,
                 recipientNickname: nil,
-                senderPeerID: "nostr:\(event.pubkey.prefix(8))",
+                senderPeerID: "nostr:\(event.pubkey.prefix(TransportConfig.nostrShortKeyDisplayLength))",
                 mentions: mentions.isEmpty ? nil : mentions
             )
             Task { @MainActor in
@@ -1444,7 +1445,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             // pared back logging: subscribe debug only
             SecureLogger.log("GeoDM: subscribing DMs pub=\(id.publicKeyHex.prefix(8))… sub=\(dmSub)",
                             category: SecureLogger.session, level: .debug)
-            let dmFilter = NostrFilter.giftWrapsFor(pubkey: id.publicKeyHex, since: Date().addingTimeInterval(-86400))
+            let dmFilter = NostrFilter.giftWrapsFor(pubkey: id.publicKeyHex, since: Date().addingTimeInterval(-TransportConfig.nostrDMSubscribeLookbackSeconds))
             NostrRelayManager.shared.subscribe(filter: dmFilter, id: dmSub) { [weak self] giftWrap in
                 guard let self = self else { return }
                 // Dedup basic
@@ -1593,7 +1594,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
 
     private func refreshGeohashPeople() {
         guard let gh = currentGeohash else { geohashPeople = []; return }
-        let cutoff = Date().addingTimeInterval(-5 * 60)
+        let cutoff = Date().addingTimeInterval(-TransportConfig.uiRecentCutoffFiveMinutesSeconds)
         var map = geoParticipants[gh] ?? [:]
         // Prune expired entries
         map = map.filter { $0.value >= cutoff }
@@ -1628,7 +1629,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     @MainActor
     func visibleGeohashPeople() -> [GeoPerson] {
         guard let gh = currentGeohash else { return [] }
-        let cutoff = Date().addingTimeInterval(-5 * 60)
+        let cutoff = Date().addingTimeInterval(-TransportConfig.uiRecentCutoffFiveMinutesSeconds)
         let map = (geoParticipants[gh] ?? [:])
             .filter { $0.value >= cutoff }
             .filter { !SecureIdentityStateManager.shared.isNostrBlocked(pubkeyHexLowercased: $0.key) }
@@ -1640,7 +1641,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     /// Returns the current participant count for a specific geohash, using the 5-minute activity window.
     @MainActor
     func geohashParticipantCount(for geohash: String) -> Int {
-        let cutoff = Date().addingTimeInterval(-5 * 60)
+        let cutoff = Date().addingTimeInterval(-TransportConfig.uiRecentCutoffFiveMinutesSeconds)
         let map = geoParticipants[geohash] ?? [:]
         return map.values.filter { $0 >= cutoff }.count
     }
@@ -1688,7 +1689,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         }
         
         // Remove geohash DM conversation if exists
-        let convKey = "nostr_" + String(hex.prefix(16))
+        let convKey = "nostr_" + String(hex.prefix(TransportConfig.nostrConvKeyPrefixLength))
         if privateChats[convKey] != nil {
             privateChats.removeValue(forKey: convKey)
             unreadPrivateMessages.remove(convKey)
@@ -1724,7 +1725,11 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         for gh in toAdd {
             let subID = "geo-sample-\(gh)"
             geoSamplingSubs[subID] = gh
-            let filter = NostrFilter.geohashEphemeral(gh, since: Date().addingTimeInterval(-300), limit: 100)
+            let filter = NostrFilter.geohashEphemeral(
+                gh,
+                since: Date().addingTimeInterval(-TransportConfig.nostrGeohashSampleLookbackSeconds),
+                limit: TransportConfig.nostrGeohashSampleLimit
+            )
             let subRelays = GeoRelayDirectory.shared.closestRelays(toGeohash: gh, count: 5)
             NostrRelayManager.shared.subscribe(filter: filter, id: subID, relayUrls: subRelays) { [weak self] event in
                 guard let self = self else { return }
@@ -1927,7 +1932,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     // MARK: - Geohash DMs initiation
     @MainActor
     func startGeohashDM(withPubkeyHex hex: String) {
-        let convKey = "nostr_" + String(hex.prefix(16))
+        let convKey = "nostr_" + String(hex.prefix(TransportConfig.nostrConvKeyPrefixLength))
         nostrKeyMapping[convKey] = hex
         selectedPrivateChatPeer = convKey
     }
@@ -2397,7 +2402,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             // Try immediately
             self.markPrivateMessagesAsRead(from: peerID)
             // And again with a delay
-            DispatchQueue.main.asyncAfter(deadline: .now() + 0.2) {
+            DispatchQueue.main.asyncAfter(deadline: .now() + TransportConfig.uiAnimationMediumSeconds) {
                 self.markPrivateMessagesAsRead(from: peerID)
             }
         }
@@ -2462,13 +2467,8 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                             teleported: LocationChannelManager.shared.teleported
                         )
                         let targetRelays = GeoRelayDirectory.shared.closestRelays(toGeohash: ch.geohash, count: 5)
-                        if targetRelays.isEmpty {
-                    let targetRelays = GeoRelayDirectory.shared.closestRelays(toGeohash: ch.geohash, count: 5)
                         if targetRelays.isEmpty {
                             SecureLogger.log("Geo: no geohash relays available for \(ch.geohash); not sending", category: SecureLogger.session, level: .warning)
-                    } else {
-                        NostrRelayManager.shared.sendEvent(event, to: targetRelays)
-                    }
                         } else {
                             NostrRelayManager.shared.sendEvent(event, to: targetRelays)
                         }
@@ -2495,7 +2495,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
     }
     
     @objc private func appWillResignActive() {
-        userDefaults.synchronize()
+        // No-op; avoid forcing synchronize on resign
     }
     
     @objc func applicationWillTerminate() {
@@ -2508,15 +2508,14 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         // Verify identity key is still there
         _ = KeychainManager.shared.verifyIdentityKeyExists()
         
-        userDefaults.synchronize()
+        // No need to force synchronize here
         
         // Verify identity key after save
         _ = KeychainManager.shared.verifyIdentityKeyExists()
     }
     
     @objc private func appWillTerminate() {
-        
+        // No need to force synchronize here
-        userDefaults.synchronize()
     }
     
     @MainActor
@@ -2682,7 +2681,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             }().lowercased()
             // Try exact match against cached geoNicknames (pubkey -> nickname)
             if let pub = geoNicknames.first(where: { (_, nick) in nick.lowercased() == base })?.key {
-                let convKey = "nostr_" + String(pub.prefix(16))
+                let convKey = "nostr_" + String(pub.prefix(TransportConfig.nostrConvKeyPrefixLength))
                 nostrKeyMapping[convKey] = pub
                 return convKey
             }
@@ -2761,14 +2760,13 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         // This will force creation of a new identity (new fingerprint) on next launch
         meshService.emergencyDisconnectAll()
         
-        // Force immediate UserDefaults synchronization
+        // No need to force UserDefaults synchronization
-        userDefaults.synchronize()
         
         // Reinitialize Nostr with new identity
         // This will generate new Nostr keys derived from new Noise keys
         Task { @MainActor in
             // Small delay to ensure cleanup completes
-            try? await Task.sleep(nanoseconds: 100_000_000) // 0.1 seconds
+            try? await Task.sleep(nanoseconds: TransportConfig.uiAsyncShortSleepNs) // 0.1 seconds
             
             // Reinitialize Nostr relay manager with new identity
             nostrRelayManager = NostrRelayManager()
@@ -2938,7 +2936,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                 // In geohash channels, compare against our per-geohash nostr short ID
                 if case .location(let ch) = activeChannel, spid.hasPrefix("nostr:") {
                     if let myGeo = try? NostrIdentityBridge.deriveIdentity(forGeohash: ch.geohash) {
-                        return spid == "nostr:\(myGeo.publicKeyHex.prefix(8))"
+                        return spid == "nostr:\(myGeo.publicKeyHex.prefix(TransportConfig.nostrShortKeyDisplayLength))"
                     }
                 }
                 return spid == meshService.myPeerID
@@ -3489,7 +3487,9 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         var hue = Double(djb2(seed) % 360) / 360.0
         // Avoid orange (~30°) reserved for self
         let orange = 30.0 / 360.0
-        if abs(hue - orange) < 0.05 { hue = fmod(hue + 0.12, 1.0) }
+        if abs(hue - orange) < TransportConfig.uiColorHueAvoidanceDelta {
+            hue = fmod(hue + TransportConfig.uiColorHueOffset, 1.0)
+        }
         let saturation: Double = isDark ? 0.80 : 0.70
         let brightness: Double = isDark ? 0.75 : 0.45
         let c = Color(hue: hue, saturation: saturation, brightness: brightness)
@@ -3699,7 +3699,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         // Load verified fingerprints directly from secure storage
         verifiedFingerprints = SecureIdentityStateManager.shared.getVerifiedFingerprints()
         // Log snapshot for debugging persistence
-        let sample = Array(verifiedFingerprints.prefix(3)).map { $0.prefix(8) }.joined(separator: ", ")
+        let sample = Array(verifiedFingerprints.prefix(TransportConfig.uiFingerprintSampleCount)).map { $0.prefix(8) }.joined(separator: ", ")
         SecureLogger.log("🔐 Verified loaded: \(verifiedFingerprints.count) [\(sample)]", category: SecureLogger.security, level: .info)
         // Also log any offline favorites and whether we consider them verified
         let offlineFavorites = unifiedPeerService.favorites.filter { !$0.isConnected }
@@ -3997,7 +3997,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                let favoriteStatus = FavoritesPersistenceService.shared.getFavoriteStatus(for: peer.noisePublicKey),
                favoriteStatus.isFavorite {
                 // Resend favorite notification with our Nostr key after a short delay
-                try? await Task.sleep(nanoseconds: 500_000_000) // 0.5 seconds
+                try? await Task.sleep(nanoseconds: TransportConfig.uiAsyncMediumSleepNs) // 0.5 seconds
                 meshService.sendFavoriteNotification(to: peerID, isFavorite: true)
                 SecureLogger.log("📤 Resent favorite notification to reconnected peer \(peerID)", 
                                 category: SecureLogger.session, level: .debug)
@@ -4411,7 +4411,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         // Subscribe to Nostr messages
         let filter = NostrFilter.giftWrapsFor(
             pubkey: currentIdentity.publicKeyHex,
-            since: Date().addingTimeInterval(-86400)  // Last 24 hours
+            since: Date().addingTimeInterval(-TransportConfig.nostrDMSubscribeLookbackSeconds)  // Last 24 hours
         )
         
         nostrRelayManager?.subscribe(filter: filter, id: "chat-messages") { [weak self] event in
@@ -4482,7 +4482,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             let messageTimestamp = Date(timeIntervalSince1970: TimeInterval(rumorTimestamp))
             let senderNickname = (actualSenderNoiseKey != nil) ? (FavoritesPersistenceService.shared.getFavoriteStatus(for: actualSenderNoiseKey!)?.peerNickname ?? "Unknown") : "Unknown"
             // Stable target ID if we know Noise key; otherwise temporary Nostr-based peer
-            let targetPeerID = actualSenderNoiseKey?.hexEncodedString() ?? ("nostr_" + senderPubkey.prefix(16))
+            let targetPeerID = actualSenderNoiseKey?.hexEncodedString() ?? ("nostr_" + senderPubkey.prefix(TransportConfig.nostrConvKeyPrefixLength))
 
             switch noisePayload.type {
             case .privateMessage:
@@ -4805,7 +4805,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
         
         // For now, create a temporary peer ID based on Nostr pubkey
         // This allows the message to be displayed even without Noise key mapping
-        let tempPeerID = "nostr_" + senderPubkey.prefix(16)
+        let tempPeerID = "nostr_" + senderPubkey.prefix(TransportConfig.nostrConvKeyPrefixLength)
         
         // Check if we're viewing this unknown sender's chat
         let isViewingThisChat = selectedPrivateChatPeer == tempPeerID
@@ -5033,7 +5033,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             var oldPeerIDsToRemove: [String] = []
             
             // Only migrate messages from the last 24 hours to prevent old messages from flooding
-            let cutoffTime = Date().addingTimeInterval(-24 * 60 * 60)
+            let cutoffTime = Date().addingTimeInterval(-TransportConfig.uiMigrationCutoffSeconds)
             
             for (oldPeerID, messages) in privateChats {
                 if oldPeerID != peerID {
@@ -5257,7 +5257,7 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             }
             
             // Mark other messages as read
-            DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) { [weak self] in
+            DispatchQueue.main.asyncAfter(deadline: .now() + TransportConfig.uiReadReceiptRetryShortSeconds) { [weak self] in
                 self?.markPrivateMessagesAsRead(from: peerID)
             }
         }
@@ -5493,7 +5493,7 @@ private func checkForMentions(_ message: BitchatMessage) {
             impactFeedback.prepare()
             
             for i in 0..<8 {
-                DispatchQueue.main.asyncAfter(deadline: .now() + Double(i) * 0.15) {
+                DispatchQueue.main.asyncAfter(deadline: .now() + Double(i) * TransportConfig.uiBatchDispatchStaggerSeconds) {
                     impactFeedback.impactOccurred()
                 }
             }

bitchat/Views/ContentView.swift

@@ -100,14 +100,14 @@ struct ContentView: View {
                                 .onEnded { value in
                                     let translation = value.translation.width.isNaN ? 0 : value.translation.width
                                     let velocity = value.velocity.width.isNaN ? 0 : value.velocity.width
-                                    if translation > 50 || (translation > 30 && velocity > 300) {
+                                    if translation > TransportConfig.uiBackSwipeTranslationLarge || (translation > TransportConfig.uiBackSwipeTranslationSmall && velocity > TransportConfig.uiBackSwipeVelocityThreshold) {
-                                        withAnimation(.easeOut(duration: 0.2)) {
+                                        withAnimation(.easeOut(duration: TransportConfig.uiAnimationMediumSeconds)) {
                                             showPrivateChat = false
                                             backSwipeOffset = 0
                                             viewModel.endPrivateChat()
                                         }
                                     } else {
-                                        withAnimation(.easeOut(duration: 0.15)) {
+                                        withAnimation(.easeOut(duration: TransportConfig.uiAnimationShortSeconds)) {
                                             backSwipeOffset = 0
                                         }
                                     }
@@ -121,7 +121,7 @@ struct ContentView: View {
                     Color.clear
                         .contentShape(Rectangle())
                         .onTapGesture {
-                            withAnimation(.easeInOut(duration: 0.2)) {
+            withAnimation(.easeInOut(duration: TransportConfig.uiAnimationMediumSeconds)) {
                                 showSidebar = false
                                 sidebarDragOffset = 0
                             }
@@ -151,14 +151,14 @@ struct ContentView: View {
                     let width = geometry.size.width.isNaN ? 0 : max(0, geometry.size.width)
                     return showSidebar ? -dragOffset : width - dragOffset
                 }())
-                .animation(.easeInOut(duration: 0.25), value: showSidebar)
+                .animation(.easeInOut(duration: TransportConfig.uiAnimationSidebarSeconds), value: showSidebar)
             }
         }
         #if os(macOS)
         .frame(minWidth: 600, minHeight: 400)
         #endif
         .onChange(of: viewModel.selectedPrivateChatPeer) { newValue in
-            withAnimation(.easeInOut(duration: 0.2)) {
+            withAnimation(.easeInOut(duration: TransportConfig.uiAnimationMediumSeconds)) {
                 showPrivateChat = newValue != nil
             }
         }
@@ -195,7 +195,7 @@ struct ContentView: View {
                     } else {
                         viewModel.startPrivateChat(with: peerID)
                     }
-                    withAnimation(.easeInOut(duration: 0.2)) {
+                    withAnimation(.easeInOut(duration: TransportConfig.uiAnimationMediumSeconds)) {
                         showSidebar = false
                         sidebarDragOffset = 0
                     }
@@ -264,7 +264,7 @@ struct ContentView: View {
                     
                     // Implement windowing with adjustable window count per chat
                     let currentWindowCount: Int = {
-                        if let peer = privatePeer { return windowCountPrivate[peer] ?? 300 }
+                        if let peer = privatePeer { return windowCountPrivate[peer] ?? TransportConfig.uiWindowInitialCountPrivate }
                         return windowCountPublic
                     }()
                     let windowedMessages = messages.suffix(currentWindowCount)
@@ -296,11 +296,11 @@ struct ContentView: View {
                                     let cashuTokens = message.content.extractCashuTokens()
                                     let lightningLinks = message.content.extractLightningLinks()
                                     HStack(alignment: .top, spacing: 0) {
-                                        let isLong = (message.content.count > 2000 || message.content.hasVeryLongToken(threshold: 512)) && cashuTokens.isEmpty
+                                        let isLong = (message.content.count > TransportConfig.uiLongMessageLengthThreshold || message.content.hasVeryLongToken(threshold: TransportConfig.uiVeryLongTokenThreshold)) && cashuTokens.isEmpty
                                         let isExpanded = expandedMessageIDs.contains(message.id)
                                         Text(viewModel.formatMessageAsText(message, colorScheme: colorScheme))
                                             .fixedSize(horizontal: false, vertical: true)
-                                            .lineLimit(isLong && !isExpanded ? 30 : nil)
+                                            .lineLimit(isLong && !isExpanded ? TransportConfig.uiLongMessageLineLimit : nil)
                                             .frame(maxWidth: .infinity, alignment: .leading)
                                         
                                         // Delivery status indicator for private messages
@@ -312,7 +312,7 @@ struct ContentView: View {
                                     }
                                     
                                     // Expand/Collapse for very long messages
-                                    if (message.content.count > 2000 || message.content.hasVeryLongToken(threshold: 512)) && cashuTokens.isEmpty {
+                                    if (message.content.count > TransportConfig.uiLongMessageLengthThreshold || message.content.hasVeryLongToken(threshold: TransportConfig.uiVeryLongTokenThreshold)) && cashuTokens.isEmpty {
                                         let isExpanded = expandedMessageIDs.contains(message.id)
                                         Button(isExpanded ? "show less" : "show more") {
                                             if isExpanded { expandedMessageIDs.remove(message.id) }
@@ -371,7 +371,7 @@ struct ContentView: View {
                             }
                             // Infinite scroll up: when top row appears, increase window and preserve anchor
                             if message.id == windowedMessages.first?.id, messages.count > windowedMessages.count {
-                                let step = 200
+                                let step = TransportConfig.uiWindowStepCount
                                 let contextKey: String = {
                                     if let peer = privatePeer { return "dm:\(peer)" }
                                     switch locationManager.selectedChannel {
@@ -381,7 +381,7 @@ struct ContentView: View {
                                 }()
                                 let preserveID = "\(contextKey)|\(message.id)"
                                 if let peer = privatePeer {
-                                    let current = windowCountPrivate[peer] ?? 300
+                                    let current = windowCountPrivate[peer] ?? TransportConfig.uiWindowInitialCountPrivate
                                     let newCount = min(messages.count, current + step)
                                     if newCount != current {
                                         windowCountPrivate[peer] = newCount
@@ -540,7 +540,7 @@ struct ContentView: View {
                     }
                     // Throttle scroll animations to prevent excessive UI updates
                     let now = Date()
-                    if now.timeIntervalSince(lastScrollTime) > 0.5 {
+                    if now.timeIntervalSince(lastScrollTime) > TransportConfig.uiScrollThrottleSeconds {
                         // Immediate scroll if enough time has passed
                         lastScrollTime = now
                         let contextKey: String = {
@@ -557,7 +557,7 @@ struct ContentView: View {
                     } else {
                         // Schedule a delayed scroll
                         scrollThrottleTimer?.invalidate()
-                        scrollThrottleTimer = Timer.scheduledTimer(withTimeInterval: 0.5, repeats: false) { _ in
+                        scrollThrottleTimer = Timer.scheduledTimer(withTimeInterval: TransportConfig.uiScrollThrottleSeconds, repeats: false) { _ in
                             lastScrollTime = Date()
                         let contextKey: String = {
                             switch locationManager.selectedChannel {
@@ -589,7 +589,7 @@ struct ContentView: View {
                     }
                     // Same throttling for private chats
                     let now = Date()
-                    if now.timeIntervalSince(lastScrollTime) > 0.5 {
+                    if now.timeIntervalSince(lastScrollTime) > TransportConfig.uiScrollThrottleSeconds {
                         lastScrollTime = now
                         let contextKey = "dm:\(peerID)"
                         let count = windowCountPrivate[peerID] ?? 300
@@ -599,7 +599,7 @@ struct ContentView: View {
                         }
                     } else {
                         scrollThrottleTimer?.invalidate()
-                        scrollThrottleTimer = Timer.scheduledTimer(withTimeInterval: 0.5, repeats: false) { _ in
+                        scrollThrottleTimer = Timer.scheduledTimer(withTimeInterval: TransportConfig.uiScrollThrottleSeconds, repeats: false) { _ in
                             lastScrollTime = Date()
                             let contextKey = "dm:\(peerID)"
                             let count = windowCountPrivate[peerID] ?? 300
@@ -619,7 +619,7 @@ struct ContentView: View {
                     break
                 case .location(let ch):
                     // Reset window size
-                    windowCountPublic = 300
+                    windowCountPublic = TransportConfig.uiWindowInitialCountPublic
                     let contextKey = "geo:\(ch.geohash)"
                     let last = viewModel.messages.suffix(windowCountPublic).last?.id
                     let target = last.map { "\(contextKey)|\($0)" }
@@ -635,11 +635,11 @@ struct ContentView: View {
                     // Try multiple times to ensure read receipts are sent
                     viewModel.markPrivateMessagesAsRead(from: peerID)
                     
-                    DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
+                    DispatchQueue.main.asyncAfter(deadline: .now() + TransportConfig.uiReadReceiptRetryShortSeconds) {
                         viewModel.markPrivateMessagesAsRead(from: peerID)
                     }
                     
-                    DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
+                    DispatchQueue.main.asyncAfter(deadline: .now() + TransportConfig.uiReadReceiptRetryLongSeconds) {
                         viewModel.markPrivateMessagesAsRead(from: peerID)
                     }
                 }
@@ -859,7 +859,7 @@ struct ContentView: View {
         }
         .onAppear {
             // Delay keyboard focus to avoid iOS constraint warnings
-            DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
+            DispatchQueue.main.asyncAfter(deadline: .now() + TransportConfig.uiReadReceiptRetryShortSeconds) {
                 isTextFieldFocused = true
             }
         }
@@ -925,7 +925,7 @@ struct ContentView: View {
                                  secondaryTextColor: secondaryTextColor,
                                  onTapPeer: { peerID in
                                      viewModel.startPrivateChat(with: peerID)
-                                     withAnimation(.easeInOut(duration: 0.2)) {
+                                     withAnimation(.easeInOut(duration: TransportConfig.uiAnimationMediumSeconds)) {
                                          showSidebar = false
                                          sidebarDragOffset = 0
                                      }
@@ -973,7 +973,7 @@ struct ContentView: View {
                 .onEnded { value in
                     let translation = value.translation.width.isNaN ? 0 : value.translation.width
                     let velocity = value.velocity.width.isNaN ? 0 : value.velocity.width
-                    withAnimation(.easeOut(duration: 0.2)) {
+                    withAnimation(.easeOut(duration: TransportConfig.uiAnimationMediumSeconds)) {
                         if !showSidebar {
                             if translation < -100 || (translation < -50 && velocity < -500) {
                                 showSidebar = true
@@ -1153,7 +1153,7 @@ struct ContentView: View {
                 // QR moved to the PEOPLE header in the sidebar when on mesh channel
             }
             .onTapGesture {
-                withAnimation(.easeInOut(duration: 0.2)) {
+                withAnimation(.easeInOut(duration: TransportConfig.uiAnimationMediumSeconds)) {
                     showSidebar.toggle()
                     sidebarDragOffset = 0
                 }
@@ -1294,7 +1294,7 @@ struct ContentView: View {
                     // Left and right buttons positioned with HStack
                     HStack {
                         Button(action: {
-                            withAnimation(.easeInOut(duration: 0.2)) {
+                            withAnimation(.easeInOut(duration: TransportConfig.uiAnimationMediumSeconds)) {
                                 showPrivateChat = false
                                 viewModel.endPrivateChat()
                             }

bitchatShareExtension/ShareViewController.swift

@@ -153,13 +153,13 @@ final class ShareViewController: UIViewController {
         userDefaults.set(content, forKey: "sharedContent")
         userDefaults.set(type, forKey: "sharedContentType")
         userDefaults.set(Date(), forKey: "sharedContentDate")
-        userDefaults.synchronize()
+        // No need to force synchronize; the system persists changes
     }
 
     private func finishWithMessage(_ msg: String) {
         statusLabel.text = msg
         // Complete shortly after showing status
-        DispatchQueue.main.asyncAfter(deadline: .now() + 0.3) {
+        DispatchQueue.main.asyncAfter(deadline: .now() + TransportConfig.uiShareExtensionDismissDelaySeconds) {
             self.extensionContext?.completeRequest(returningItems: nil, completionHandler: nil)
         }
     }