refactor: enhance push notification routing with full payload handling and add socket connection state management

lib/core/services/push_notification_service.dart

@@ -1,3 +1,4 @@
+import 'dart:convert';
 import 'dart:io';
 
 import 'package:firebase_core/firebase_core.dart';
@@ -27,7 +28,38 @@ class PushNotificationService {
   bool _initialized = false;
 
   /// Callback when user taps a notification — set by the app to navigate.
-  void Function(String? actionUrl)? onNotificationTap;
+  /// Receives the full FCM data payload so the app can route by `type`
+  /// (e.g. 'message' → open chat) instead of only relying on `actionUrl`.
+  ///
+  /// When this setter is assigned and a pending tap was buffered (because the
+  /// terminated-state tap fired before the app UI was ready), the buffered
+  /// tap is replayed immediately.
+  void Function(Map<String, dynamic> data)? _onNotificationTap;
+  Map<String, dynamic>? _pendingTap;
+
+  set onNotificationTap(void Function(Map<String, dynamic> data)? handler) {
+    _onNotificationTap = handler;
+    // Replay any buffered tap once a listener is attached
+    if (handler != null && _pendingTap != null) {
+      final buffered = _pendingTap!;
+      _pendingTap = null;
+      // Defer to next microtask so the caller's initState finishes first
+      Future.microtask(() => handler(buffered));
+    }
+  }
+
+  void Function(Map<String, dynamic> data)? get onNotificationTap =>
+      _onNotificationTap;
+
+  void _dispatchTap(Map<String, dynamic> data) {
+    final handler = _onNotificationTap;
+    if (handler != null) {
+      handler(data);
+    } else {
+      // No listener yet — buffer for replay once one attaches
+      _pendingTap = data;
+    }
+  }
 
   /// The conversation ID currently being viewed — suppress message push
   /// notifications for this conversation to avoid self-notifications.
@@ -116,7 +148,17 @@ class PushNotificationService {
       ),
       onDidReceiveNotificationResponse: (response) {
         final payload = response.payload;
-        onNotificationTap?.call(payload);
+        if (payload == null || payload.isEmpty) {
+          _dispatchTap(const {});
+          return;
+        }
+        try {
+          final data = jsonDecode(payload) as Map<String, dynamic>;
+          _dispatchTap(data);
+        } catch (_) {
+          // Legacy payloads may be a bare actionUrl string
+          _dispatchTap({'actionUrl': payload});
+        }
       },
     );
   }
@@ -200,15 +242,16 @@ class PushNotificationService {
             icon: '@mipmap/ic_launcher',
           ),
         ),
-        payload: message.data['actionUrl'],
+        // Encode the full FCM data as JSON so the tap handler can route
+        // by `type` (e.g. open the specific chat for message notifications).
+        payload: jsonEncode(message.data),
       );
     }
   }
 
   void _onMessageOpenedApp(RemoteMessage message) {
     debugPrint('[FCM] Notification tap: ${message.data}');
-    final actionUrl = message.data['actionUrl'] as String?;
-    onNotificationTap?.call(actionUrl);
+    _dispatchTap(Map<String, dynamic>.from(message.data));
   }
 
   /// Unregister FCM token from backend (call on logout).