Implement robust notification deep linking

- Create SecureChatLoaderScreen for linking to conversations by ID
- Add /secure-chat/:id route to AppRoutes
- Update NotificationService to use AppRoutes.router for all navigation
- Fix Follow and Post navigation routes in NotificationService
- Decouple notification handling from manual Navigator pushes

sojorn_app/lib/routes/app_routes.dart

@@ -19,6 +19,7 @@ import '../screens/profile/blocked_users_screen.dart';
 import '../screens/auth/auth_gate.dart';
 import '../screens/discover/discover_screen.dart';
 import '../screens/secure_chat/secure_chat_full_screen.dart';
+import '../screens/secure_chat/secure_chat_loader_screen.dart';
 import '../screens/post/threaded_conversation_screen.dart';
 
 /// App routing config (GoRouter).
@@ -65,6 +66,15 @@ class AppRoutes {
         path: secureChat,
         parentNavigatorKey: rootNavigatorKey,
         builder: (_, __) => const SecureChatFullScreen(),
+        routes: [
+          GoRoute(
+            path: ':id',
+            parentNavigatorKey: rootNavigatorKey,
+            builder: (_, state) => SecureChatLoaderScreen(
+              conversationId: state.pathParameters['id'] ?? '',
+            ),
+          ),
+        ],
       ),
       GoRoute(
         path: '$postPrefix/:id',

sojorn_app/lib/screens/secure_chat/secure_chat_loader_screen.dart

@@ -0,0 +1,84 @@
+import 'package:flutter/material.dart';
+import '../../services/secure_chat_service.dart';
+import '../../theme/app_theme.dart';
+import 'secure_chat_screen.dart';
+
+/// Loading wrapper to fetch conversation data before showing chat screen
+class SecureChatLoaderScreen extends StatefulWidget {
+  final String conversationId;
+
+  const SecureChatLoaderScreen({
+    super.key,
+    required this.conversationId,
+  });
+
+  @override
+  State<SecureChatLoaderScreen> createState() => _SecureChatLoaderScreenState();
+}
+
+class _SecureChatLoaderScreenState extends State<SecureChatLoaderScreen> {
+  String? _error;
+
+  @override
+  void initState() {
+    super.initState();
+    _loadConversation();
+  }
+
+  Future<void> _loadConversation() async {
+    try {
+      final conversation = await SecureChatService.instance
+          .getConversationById(widget.conversationId);
+
+      if (!mounted) return;
+
+      if (conversation != null) {
+        // Replace this loader with the actual chat screen
+        Navigator.of(context).pushReplacement(
+          MaterialPageRoute(
+            builder: (_) => SecureChatScreen(conversation: conversation),
+          ),
+        );
+      } else {
+        setState(() {
+          _error = 'Conversation not found';
+        });
+      }
+    } catch (e) {
+      if (mounted) {
+        setState(() {
+          _error = 'Failed to load conversation: $e';
+        });
+      }
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    if (_error != null) {
+      return Scaffold(
+        appBar: AppBar(title: const Text('Error')),
+        body: Center(
+          child: Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: [
+              Text(_error!, style: TextStyle(color: AppTheme.error)),
+              const SizedBox(height: 16),
+              ElevatedButton(
+                onPressed: () => Navigator.of(context).pop(),
+                child: const Text('Go Back'),
+              ),
+            ],
+          ),
+        ),
+      );
+    }
+
+    return Scaffold(
+      backgroundColor: AppTheme.scaffoldBg,
+      body: const Center(
+        child: CircularProgressIndicator(),
+      ),
+    );
+  }
+}

sojorn_app/lib/services/notification_service.dart

@@ -10,7 +10,6 @@ import 'package:permission_handler/permission_handler.dart';
 import '../config/firebase_web_config.dart';
 import '../routes/app_routes.dart';
 import '../services/secure_chat_service.dart';
-import '../screens/secure_chat/secure_chat_screen.dart';
 import 'api_service.dart';
 
 /// NotificationPreferences model
@@ -465,15 +464,13 @@ class NotificationService {
 
   Future<void> _handleMessageOpen(RemoteMessage message) async {
     final data = message.data;
+    // Try to get type from data, fallback to notification title parsing if needed
     final type = data['type'] as String?;
     
     debugPrint('[FCM] Handling message open - type: $type, data: $data');
 
-    final navigator = AppRoutes.rootNavigatorKey.currentState;
-    if (navigator == null) {
-      debugPrint('[FCM] Navigator not available');
-      return;
-    }
+    // Use the router directly for reliability
+    final router = AppRoutes.router;
 
     switch (type) {
       case 'chat':
@@ -482,6 +479,8 @@ class NotificationService {
         final conversationId = data['conversation_id'];
         if (conversationId != null) {
           await _openConversation(conversationId.toString());
+        } else {
+          router.go(AppRoutes.secureChat);
         }
         break;
 
@@ -495,7 +494,7 @@ class NotificationService {
         final postId = data['post_id'] ?? data['beacon_id'];
         final target = data['target'];
         if (postId != null) {
-          _navigateToPost(navigator, postId.toString(), target?.toString());
+          _navigateToPost(postId.toString(), target?.toString());
         }
         break;
 
@@ -505,9 +504,9 @@ class NotificationService {
       case 'follow_accepted':
         final followerId = data['follower_id'];
         if (followerId != null) {
-          navigator.context.push('${AppRoutes.userPrefix}/$followerId');
+          router.push('${AppRoutes.userPrefix}/$followerId');
         } else {
-          navigator.context.go(AppRoutes.profile);
+          router.go(AppRoutes.profile);
         }
         break;
 
@@ -515,50 +514,60 @@ class NotificationService {
       case 'beacon_report':
         final beaconId = data['beacon_id'] ?? data['post_id'];
         if (beaconId != null) {
-          _navigateToPost(navigator, beaconId.toString(), 'beacon_map');
+          _navigateToPost(beaconId.toString(), 'beacon_map');
         } else {
-          navigator.context.go(AppRoutes.beaconPrefix);
+          router.go(AppRoutes.beaconPrefix);
         }
         break;
 
       default:
         debugPrint('[FCM] Unknown notification type: $type');
+        // Retrieve generic target if available
+        final target = data['target'];
+        if (target != null) {
+           _handleGenericTarget(target.toString());
+        }
         break;
     }
   }
 
-  void _navigateToPost(NavigatorState navigator, String postId, String? target) {
+  void _navigateToPost(String postId, String? target) {
+    final router = AppRoutes.router;
     switch (target) {
       case 'beacon_map':
-        navigator.context.go(AppRoutes.beaconPrefix);
+        router.go(AppRoutes.beaconPrefix);
         break;
       case 'quip_feed':
-        navigator.context.go(AppRoutes.quips);
+        router.go(AppRoutes.quips);
         break;
       case 'thread_view':
       case 'main_feed':
       default:
-        navigator.context.push('${AppRoutes.postPrefix}/$postId');
+        router.push('${AppRoutes.postPrefix}/$postId');
         break;
     }
   }
 
-  Future<void> _openConversation(String conversationId) async {
-    final conversation =
-        await SecureChatService.instance.getConversationById(conversationId);
-    if (conversation == null) {
-      debugPrint('[FCM] Conversation not found: $conversationId');
-      return;
+  void _handleGenericTarget(String target) {
+    final router = AppRoutes.router;
+    switch (target) {
+      case 'secure_chat':
+        router.go(AppRoutes.secureChat);
+        break;
+      case 'profile':
+        router.go(AppRoutes.profile);
+        break;
+      case 'beacon_map':
+        router.go(AppRoutes.beaconPrefix);
+        break;
+      case 'quip_feed':
+        router.go(AppRoutes.quips);
+        break;
     }
+  }
 
-    final navigator = AppRoutes.rootNavigatorKey.currentState;
-    if (navigator == null) return;
-
-    navigator.push(
-      MaterialPageRoute(
-        builder: (_) => SecureChatScreen(conversation: conversation),
-      ),
-    );
+  void _openConversation(String conversationId) {
+    AppRoutes.router.push('${AppRoutes.secureChat}/$conversationId');
   }
 
   void dispose() {