Retry unacknowledged DMs after Noise replacement (#1462)

DMs sent through an established Noise session are retained in the durable MessageRouter outbox until an authenticated delivery/read ack, and retried under the same message ID when the peer's replacement handshake authenticates — fixing DMs silently lost into stale local sessions after a remote app restart. Mesh ack handling is peer-scoped end-to-end (alias-scoped delivery status, peer-bound markDelivered, PeerMessageKey retry state), so a colliding message ID from another conversation can no longer clear or promote foreign state; bridge-drop dedup keys are recipient-scoped with hashed persistence.

Includes review fix: acks arriving after a relaunch (durable outbox restored, conversation not) now clear the peer-scoped router entry unconditionally — only the UI status transition is gated on conversation presence — so a delivered message can no longer re-send to the attempt cap and be marked failed despite delivery. Regression test simulates the relaunch through real store persistence; the dead allowedPeerIDs parameter (unscoped-tombstone trap) is removed.

bitchatTests/ChatVerificationCoordinatorContextTests.swift

@@ -98,6 +98,7 @@ private final class MockChatVerificationContext: ChatVerificationContext {
     private(set) var installedCallbacks: (onPeerAuthenticated: (PeerID, String) -> Void, onHandshakeRequired: (PeerID) -> Void)?
     private(set) var triggeredHandshakes: [PeerID] = []
     private(set) var privateMediaAuthenticatedPeers: [PeerID] = []
+    private(set) var securePrivateMessageRetryAliases: [[PeerID]] = []
     private(set) var sentChallenges: [(peerID: PeerID, noiseKeyHex: String, nonceA: Data)] = []
     private(set) var sentResponses: [(peerID: PeerID, noiseKeyHex: String, nonceA: Data)] = []
 
@@ -118,6 +119,10 @@ private final class MockChatVerificationContext: ChatVerificationContext {
         privateMediaAuthenticatedPeers.append(peerID)
     }
 
+    func retrySecurePrivateMessagesAfterAuthentication(for peerIDAliases: [PeerID]) {
+        securePrivateMessageRetryAliases.append(peerIDAliases)
+    }
+
     func sendVerifyChallenge(to peerID: PeerID, noiseKeyHex: String, nonceA: Data) {
         sentChallenges.append((peerID, noiseKeyHex, nonceA))
     }
@@ -269,6 +274,10 @@ struct ChatVerificationCoordinatorContextTests {
         let peerID = PeerID(str: "1122334455667788")
         let noiseKey = Data(repeating: 0x33, count: 32)
         context.noiseSessionKeysByPeerID[peerID] = noiseKey
+        context.cacheStablePeerID(
+            PeerID(hexData: Data(repeating: 0x44, count: 32)),
+            for: peerID
+        )
         context.verifiedFingerprints = ["fp-verified"]
 
         coordinator.setupNoiseCallbacks()
@@ -279,9 +288,11 @@ struct ChatVerificationCoordinatorContextTests {
         callbacks?.onPeerAuthenticated(peerID, "fp-verified")
         await waitForMainQueue()
         #expect(context.encryptionStatuses[peerID] == .noiseVerified)
-        #expect(context.stablePeerIDCache[peerID] == PeerID(hexData: noiseKey))
+        let stablePeerID = PeerID(hexData: noiseKey)
+        #expect(context.stablePeerIDCache[peerID] == stablePeerID)
         #expect(context.invalidatedEncryptionCachePeers.contains(peerID))
         #expect(context.privateMediaAuthenticatedPeers == [peerID])
+        #expect(context.securePrivateMessageRetryAliases == [[peerID, stablePeerID]])
 
         // Handshake required -> handshaking status.
         callbacks?.onHandshakeRequired(peerID)