feat: trigger local notification directly from incoming WebSocket new_message event

whatsapp_app/lib/services/firebase_service.dart

@@ -153,6 +153,36 @@ class FirebaseService extends GetxService {
     );
   }
 
+  void showLocalNotificationFromData(Map<String, dynamic> data) {
+    final chatId = data['chatId'];
+    final name = data['name'] ?? 'WhatsApp';
+    final body = data['body'] ?? 'New Message';
+
+    // Smart Notification: Only show if we are NOT currently in this chat
+    final activeChatId = Get.find<WhatsAppService>().activeChatId.value;
+    if (chatId != null && activeChatId == chatId) {
+      return; // Silent
+    }
+
+    const androidDetails = AndroidNotificationDetails(
+      'whatsapp_channel',
+      'WhatsApp Messages',
+      importance: Importance.max,
+      priority: Priority.high,
+      ticker: 'ticker',
+    );
+    const iosDetails = DarwinNotificationDetails();
+    const details = NotificationDetails(android: androidDetails, iOS: iosDetails);
+
+    _localNotifications.show(
+      DateTime.now().microsecond,
+      name,
+      body,
+      details,
+      payload: jsonEncode({'chatId': chatId, 'name': name}),
+    );
+  }
+
   void _onNotificationTap(NotificationResponse response) {
     if (response.payload != null) {
       final data = jsonDecode(response.payload!);
@@ -165,7 +195,6 @@ class FirebaseService extends GetxService {
     final name = data['name'] ?? 'Chat';
 
     if (chatId != null) {
-      // Mock a conversation model to navigate to ChatScreen
       final dummyChat = ConversationModel(
         id: chatId,
         name: name,
@@ -176,7 +205,7 @@ class FirebaseService extends GetxService {
         isMuted: false,
       );
 
-      Get.to(() => ChatScreen(conversation: dummyChat));
+      Get.to(() => ChatScreen(conversation: dummyChat), preventDuplicates: false);
     }
   }
 }