Add iOS lifecycle hardening hooks

apps/ios/TeleTuiIOS/Sources/TeleTuiIOSSmokeTests/main.swift

@@ -9,6 +9,7 @@ struct TeleTuiIOSSmokeTests {
         try await chatDetailLoadsAndSendsMessage()
         try await messageActionsCoverEditReplyForwardReactDeleteSearchAndCopy()
         try await platformServicesCoverNotificationsMediaVoiceClipboardAndAccounts()
+        lifecycleCoordinatorDropsStaleAccountEvents()
         try await profileLoadsFromSelectedChat()
         appStorageUsesApplicationSupportStyleAccountPaths()
         print("TeleTuiIOS smoke tests passed")
@@ -141,6 +142,35 @@ struct TeleTuiIOSSmokeTests {
         precondition(switcher.activeAccount.databasePath.path.hasSuffix("/Accounts/work/tdlib"))
     }
 
+    @MainActor
+    private static func lifecycleCoordinatorDropsStaleAccountEvents() {
+        let coordinator = SessionLifecycleCoordinator(activeAccountId: "personal")
+        precondition(coordinator.shouldPollEvents)
+
+        coordinator.enterBackground()
+        precondition(!coordinator.shouldPollEvents)
+
+        coordinator.enterForeground()
+        precondition(coordinator.shouldPollEvents)
+
+        let oldGenerationEvent = ScopedSessionEvent(
+            accountId: "personal",
+            generation: coordinator.generation,
+            event: .authChanged(.ready)
+        )
+        precondition(coordinator.accepts(oldGenerationEvent))
+
+        coordinator.switchAccount(to: "work")
+        precondition(!coordinator.accepts(oldGenerationEvent))
+
+        let newGenerationEvent = ScopedSessionEvent(
+            accountId: "work",
+            generation: coordinator.generation,
+            event: .authChanged(.ready)
+        )
+        precondition(coordinator.accepts(newGenerationEvent))
+    }
+
     @MainActor
     private static func profileLoadsFromSelectedChat() async throws {
         let bridge = FakeSessionBridge(auth: .ready)