Phase 3.1: Complete mitra_app Riverpod migration (all blocs, fix auth bug)

- Migrate AuthBloc → MitraAuthNotifier (fixes stuck-loading bug: now returns
  MitraAuthInitialData when currentUser is null)
- Migrate StatusBloc → OnlineStatusNotifier (heartbeat timer + lifecycle)
- Migrate ExtensionBloc → MitraExtensionNotifier (accept/reject + goodbye)
- Migrate ChatRequestBloc → ChatRequestNotifier (WebSocket incoming requests)
- Migrate MitraChatBloc → MitraChatNotifier (WebSocket chat + messages)
- Update router to use Riverpod auth state for redirects
- Remove all flutter_bloc usage from mitra_app screens and main.dart
- MultiBlocProvider fully removed from mitra_app

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

mitra_app/lib/main.dart

@@ -1,15 +1,10 @@
 import 'package:firebase_core/firebase_core.dart';
 import 'package:firebase_messaging/firebase_messaging.dart';
 import 'package:flutter/material.dart';
-import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
-import 'package:go_router/go_router.dart';
-import 'core/api/api_client.dart';
-import 'core/auth/auth_bloc.dart';
-import 'core/status/status_bloc.dart';
-import 'core/chat/chat_request_bloc.dart';
-import 'core/chat/mitra_chat_bloc.dart';
-import 'core/chat/extension_bloc.dart';
+import 'core/api/api_client_provider.dart';
+import 'core/auth/auth_notifier.dart';
+import 'core/status/status_notifier.dart';
 import 'core/notifications/notification_service.dart';
 import 'firebase_options.dart';
 import 'router.dart';
@@ -24,85 +19,69 @@ void main() async {
   runApp(const ProviderScope(child: App()));
 }
 
-class App extends StatefulWidget {
+class App extends ConsumerStatefulWidget {
   const App({super.key});
 
   @override
-  State<App> createState() => _AppState();
+  ConsumerState<App> createState() => _AppState();
 }
 
-class _AppState extends State<App> with WidgetsBindingObserver {
-  late final ApiClient _apiClient;
-  late final AuthBloc _authBloc;
-  late final GoRouter _router;
-  late final StatusBloc _statusBloc;
-  late final ChatRequestBloc _chatRequestBloc;
+class _AppState extends ConsumerState<App> with WidgetsBindingObserver {
+  bool _fcmRegistered = false;
 
   @override
   void initState() {
     super.initState();
     WidgetsBinding.instance.addObserver(this);
-    _apiClient = ApiClient();
-    _authBloc = AuthBloc(apiClient: _apiClient)..add(AppStarted());
-    _router = buildRouter(_authBloc);
-    NotificationService.initialize(_router);
-    _statusBloc = StatusBloc(apiClient: _apiClient);
-    _chatRequestBloc = ChatRequestBloc(apiClient: _apiClient);
-    _registerFcmToken();
-  }
-
-  Future<void> _registerFcmToken() {
-    return _authBloc.stream.where((s) => s is AuthAuthenticated).first.then((_) async {
-      try {
-        final token = await FirebaseMessaging.instance.getToken();
-        if (token != null) {
-          await _apiClient.post('/api/shared/device-token', data: {'token': token});
-        }
-      } catch (_) {}
-    });
   }
 
   @override
   void dispose() {
     WidgetsBinding.instance.removeObserver(this);
-    _authBloc.close();
-    _router.dispose();
-    _statusBloc.close();
-    _chatRequestBloc.close();
     super.dispose();
   }
 
   @override
   void didChangeAppLifecycleState(AppLifecycleState state) {
     if (state == AppLifecycleState.paused || state == AppLifecycleState.detached) {
-      _statusBloc.add(AppPaused());
+      ref.read(onlineStatusProvider.notifier).onAppPaused();
     } else if (state == AppLifecycleState.resumed) {
-      _statusBloc.add(AppResumed());
+      ref.read(onlineStatusProvider.notifier).onAppResumed();
     }
   }
 
+  void _registerFcmToken() {
+    if (_fcmRegistered) return;
+    _fcmRegistered = true;
+    Future(() async {
+      try {
+        final token = await FirebaseMessaging.instance.getToken();
+        if (token != null) {
+          await ref.read(apiClientProvider).post('/api/shared/device-token', data: {'token': token});
+        }
+      } catch (_) {
+        _fcmRegistered = false;
+      }
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
-    return MultiBlocProvider(
-      providers: [
-        BlocProvider.value(value: _authBloc),
-        BlocProvider.value(value: _statusBloc),
-        BlocProvider.value(value: _chatRequestBloc),
-        BlocProvider(create: (_) => MitraChatBloc(apiClient: _apiClient)),
-        BlocProvider(create: (_) => ExtensionBloc(apiClient: _apiClient)),
-        RepositoryProvider.value(value: _apiClient),
-      ],
-      child: BlocListener<AuthBloc, AuthState>(
-        listener: (context, state) {
-          if (state is AuthAuthenticated) {
-            _statusBloc.add(StatusLoadRequested());
-          }
-        },
-        child: MaterialApp.router(
-          title: 'Halo Bestie Mitra',
-          routerConfig: _router,
-        ),
-      ),
+    // Listen for auth changes to load status and register FCM
+    ref.listen(mitraAuthProvider, (prev, next) {
+      final data = next.valueOrNull;
+      if (data is MitraAuthAuthenticatedData) {
+        ref.read(onlineStatusProvider.notifier).load();
+        _registerFcmToken();
+      }
+    });
+
+    final router = ref.watch(routerProvider);
+    NotificationService.initialize(router);
+
+    return MaterialApp.router(
+      title: 'Halo Bestie Mitra',
+      routerConfig: router,
     );
   }
 }