added firebase for notification

lib/core/services/messaging_service.dart

@@ -0,0 +1,14 @@
+import 'package:firebase_messaging/firebase_messaging.dart';
+
+import 'package:logger/logger.dart';
+
+class MessagingService {
+  //create an instance of firebase messaging
+  final _firebaseMessaging = FirebaseMessaging.instance;
+
+  Future<void> initNotifications() async {
+    await _firebaseMessaging.requestPermission();
+    final fcmToken = await _firebaseMessaging.getToken();
+    Logger().i('FCMToken: $fcmToken');
+  }
+}