Make lifecycle delayed read-pass deterministic in tests

The coordinator scheduled its delayed owner-level read pass via
DispatchQueue.main.asyncAfter, which a busy CI runner's main queue can
delay past any reasonable polling deadline. Scheduling is now an
injected context member (scheduleOnMainAfter); the ChatViewModel witness
keeps the exact asyncAfter behavior while the test mock runs the work
synchronously, eliminating the wall-clock poll entirely.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

bitchat/ViewModels/ChatLifecycleCoordinator.swift

@@ -30,6 +30,9 @@ protocol ChatLifecycleContext: AnyObject {
     func markPrivateMessagesAsRead(from peerID: PeerID)
     /// Marks the chat read in the private chat manager (sends pending mesh READ acks).
     func markChatAsRead(from peerID: PeerID)
+    /// Schedules main-actor work after a UI-timing delay. Injected so tests
+    /// can run the work synchronously instead of polling wall-clock queues.
+    func scheduleOnMainAfter(_ delay: TimeInterval, _ work: @escaping @MainActor () -> Void)
     func synchronizePrivateConversationStore()
     func addSystemMessage(_ content: String)
 
@@ -83,6 +86,14 @@ extension ChatViewModel: ChatLifecycleContext {
         privateChatManager.markAsRead(from: peerID)
     }
 
+    func scheduleOnMainAfter(_ delay: TimeInterval, _ work: @escaping @MainActor () -> Void) {
+        DispatchQueue.main.asyncAfter(deadline: .now() + delay) {
+            Task { @MainActor in
+                work()
+            }
+        }
+    }
+
     func stopMeshServices() {
         meshService.stopServices()
     }
@@ -119,12 +130,10 @@ final class ChatLifecycleCoordinator {
         markPrivateMessagesAsRead(from: peerID)
 
         let context = self.context
-        DispatchQueue.main.asyncAfter(deadline: .now() + TransportConfig.uiAnimationMediumSeconds) { [weak context] in
-            Task { @MainActor in
+        context.scheduleOnMainAfter(TransportConfig.uiAnimationMediumSeconds) { [weak context] in
             context?.markPrivateMessagesAsRead(from: peerID)
         }
     }
-    }
 
     func handleScreenshotCaptured() {
         let screenshotMessage = "* \(context.nickname) took a screenshot *"

bitchatTests/ChatLifecycleCoordinatorContextTests.swift

@@ -54,6 +54,13 @@ private final class MockChatLifecycleContext: ChatLifecycleContext {
         managerReadMarks.append(peerID)
     }
 
+    // Scheduled work runs synchronously so tests never poll wall-clock queues.
+    private(set) var scheduledDelays: [TimeInterval] = []
+    func scheduleOnMainAfter(_ delay: TimeInterval, _ work: @escaping @MainActor () -> Void) {
+        scheduledDelays.append(delay)
+        work()
+    }
+
     func synchronizePrivateConversationStore() { privateStoreSyncCount += 1 }
     func addSystemMessage(_ content: String) { systemMessages.append(content) }
 
@@ -299,10 +306,9 @@ struct ChatLifecycleCoordinatorContextTests {
         #expect(context.refreshBluetoothStateCount == 2)
         #expect(context.managerReadMarks == [peerID])
 
-        let deadline = Date().addingTimeInterval(2)
-        while context.ownerLevelReadPasses.isEmpty && Date() < deadline {
-            try? await Task.sleep(nanoseconds: 20_000_000)
-        }
+        // The mock executes scheduled work synchronously, so the delayed
+        // owner-level pass has already run - no wall-clock polling.
+        #expect(context.scheduledDelays == [TransportConfig.uiAnimationMediumSeconds])
         #expect(context.ownerLevelReadPasses == [peerID])
     }
     @Test @MainActor