Add mounted guards for BuildContext use across async gaps

lib/app_state.dart

@@ -364,6 +364,7 @@ class AppState extends ChangeNotifier {
   /// Show re-authentication dialog if needed
   Future<void> checkAndPromptReauthForMessages(BuildContext context) async {
     if (await needsReauthForMessages()) {
+      if (!context.mounted) return;
       _showReauthDialog(context);
     }
   }

lib/migrations.dart

@@ -146,7 +146,7 @@ class OneTimeMigrations {
       debugPrint('[Migration] Stack trace: $stackTrace');
       
       // Nuclear option: clear everything and show non-dismissible error dialog
-      if (context != null) {
+      if (context != null && context.mounted) {
         NuclearResetDialog.show(context, error, stackTrace);
       } else {
         // If no context available, just log and hope for the best

lib/screens/coordinators/sheet_coordinator.dart

@@ -117,9 +117,8 @@ class SheetCoordinator {
     controller.closed.then((_) {
       _addSheetHeight = 0.0;
       onStateChanged();
-      
+
       // Handle dismissal by canceling session if still active
-      final appState = context.read<AppState>();
       if (appState.session != null) {
         debugPrint('[SheetCoordinator] AddNodeSheet dismissed - canceling session');
         appState.cancelSession();
@@ -186,9 +185,8 @@ class SheetCoordinator {
       _editSheetHeight = 0.0;
       _transitioningToEdit = false;
       onStateChanged();
-      
+
       // Handle dismissal by canceling session if still active
-      final appState = context.read<AppState>();
       if (appState.editSession != null) {
         debugPrint('[SheetCoordinator] EditNodeSheet dismissed - canceling edit session');
         appState.cancelEditSession();

lib/screens/home_screen.dart

@@ -185,6 +185,7 @@ class _HomeScreenState extends State<HomeScreen> with TickerProviderStateMixin {
       
       // Run any needed migrations first
       final versionsNeedingMigration = await ChangelogService().getVersionsNeedingMigration();
+      if (!mounted) return;
       for (final version in versionsNeedingMigration) {
         await ChangelogService().runMigration(version, appState, context);
       }
@@ -209,6 +210,7 @@ class _HomeScreenState extends State<HomeScreen> with TickerProviderStateMixin {
         
         case PopupType.changelog:
           final changelogContent = await ChangelogService().getChangelogContentForDisplay();
+          if (!mounted) return;
           if (changelogContent != null) {
             await showDialog(
               context: context,
@@ -368,9 +370,11 @@ class _HomeScreenState extends State<HomeScreen> with TickerProviderStateMixin {
     );
     
     // Reset height and clear selection when sheet is dismissed
+    final appState = context.read<AppState>();
     controller.closed.then((_) {
+      if (!mounted) return;
       _sheetCoordinator.resetTagSheetHeight(() => setState(() {}));
-      context.read<AppState>().clearSuspectedLocationSelection();
+      appState.clearSuspectedLocationSelection();
     });
   }
 

lib/screens/settings/sections/node_profiles_section.dart

@@ -118,7 +118,7 @@ class NodeProfilesSection extends StatelessWidget {
     );
     
     // If user chose to create custom profile, open the profile editor
-    if (result == 'create') {
+    if (result == 'create' && context.mounted) {
       _createNewProfile(context);
     }
     // If user chose import from website, ProfileAddChoiceDialog handles opening the URL

lib/widgets/add_node_sheet.dart

@@ -89,7 +89,8 @@ class _AddNodeSheetState extends State<AddNodeSheet> {
   void _checkSubmissionGuideAndProceed(BuildContext context, AppState appState, LocalizationService locService) async {
     // Check if user has seen the submission guide
     final hasSeenGuide = await ChangelogService().hasSeenSubmissionGuide();
-    
+    if (!context.mounted) return;
+
     if (!hasSeenGuide) {
       // Show submission guide dialog first
       final shouldProceed = await showDialog<bool>(
@@ -97,13 +98,14 @@ class _AddNodeSheetState extends State<AddNodeSheet> {
         barrierDismissible: false,
         builder: (context) => const SubmissionGuideDialog(),
       );
-      
+      if (!context.mounted) return;
+
       // If user canceled the submission guide, don't proceed with submission
       if (shouldProceed != true) {
         return;
       }
     }
-    
+
     // Now proceed with proximity check
     _checkProximityOnly(context, appState, locService);
   }

lib/widgets/advanced_edit_options_sheet.dart

@@ -185,6 +185,7 @@ class AdvancedEditOptionsSheet extends StatelessWidget {
     }
     
     // No custom scheme or app launch failed - redirect to app store
+    if (!context.mounted) return;
     await _redirectToAppStore(context, editor);
   }
 

lib/widgets/download_area_dialog.dart

@@ -264,8 +264,9 @@ class _DownloadAreaDialogState extends State<DownloadAreaDialog> {
                 try {
                   final id = DateTime.now().toIso8601String().replaceAll(':', '-');
                   final appDocDir = await OfflineAreaService().getOfflineAreaDir();
+                  if (!context.mounted) return;
                   final dir = "${appDocDir.path}/$id";
-                  
+
                   // Get current tile provider info
                   final appState = context.read<AppState>();
                   final selectedProvider = appState.selectedTileProvider;
@@ -292,6 +293,7 @@ class _DownloadAreaDialogState extends State<DownloadAreaDialog> {
                     builder: (context) => const DownloadStartedDialog(),
                   );
                 } catch (e) {
+                  if (!context.mounted) return;
                   Navigator.pop(context);
                   showDialog(
                     context: context,

lib/widgets/edit_node_sheet.dart

@@ -92,7 +92,8 @@ class _EditNodeSheetState extends State<EditNodeSheet> {
   void _checkSubmissionGuideAndProceed(BuildContext context, AppState appState, LocalizationService locService) async {
     // Check if user has seen the submission guide
     final hasSeenGuide = await ChangelogService().hasSeenSubmissionGuide();
-    
+    if (!context.mounted) return;
+
     if (!hasSeenGuide) {
       // Show submission guide dialog first
       final shouldProceed = await showDialog<bool>(
@@ -100,13 +101,14 @@ class _EditNodeSheetState extends State<EditNodeSheet> {
         barrierDismissible: false,
         builder: (context) => const SubmissionGuideDialog(),
       );
-      
+      if (!context.mounted) return;
+
       // If user canceled the submission guide, don't proceed with submission
       if (shouldProceed != true) {
         return;
       }
     }
-    
+
     // Now proceed with proximity check
     _checkProximityOnly(context, appState, locService);
   }

lib/widgets/nuclear_reset_dialog.dart

@@ -96,7 +96,8 @@ class NuclearResetDialog extends StatelessWidget {
     
     // Clear all app data
     await NuclearResetService.clearEverything();
-    
+
+    if (!context.mounted) return;
     // Show non-dismissible dialog
     await showDialog(
       context: context,