feat: Implement notifications feature, enhance profile settings with new sections, and integrate Firebase configurations for multiple environments.

lib/features/notifications/data/models/notification_model.dart

@@ -0,0 +1,53 @@
+class AppNotification {
+  final String id;
+  final String userId;
+  final String type; // 'connection' | 'message' | 'system' | 'update' | 'request'
+  final String title;
+  final String description;
+  final bool read;
+  final String? actionUrl;
+  final Map<String, String>? data;
+  final DateTime createdAt;
+
+  const AppNotification({
+    required this.id,
+    required this.userId,
+    required this.type,
+    required this.title,
+    required this.description,
+    required this.read,
+    this.actionUrl,
+    this.data,
+    required this.createdAt,
+  });
+
+  factory AppNotification.fromJson(Map<String, dynamic> json) {
+    return AppNotification(
+      id: json['id'] as String,
+      userId: json['userId'] as String? ?? '',
+      type: json['type'] as String? ?? 'system',
+      title: json['title'] as String? ?? '',
+      description: json['description'] as String? ?? '',
+      read: json['read'] as bool? ?? false,
+      actionUrl: json['actionUrl'] as String?,
+      data: json['data'] != null
+          ? Map<String, String>.from(json['data'] as Map)
+          : null,
+      createdAt: DateTime.parse(json['createdAt'] as String),
+    );
+  }
+
+  AppNotification copyWith({bool? read}) {
+    return AppNotification(
+      id: id,
+      userId: userId,
+      type: type,
+      title: title,
+      description: description,
+      read: read ?? this.read,
+      actionUrl: actionUrl,
+      data: data,
+      createdAt: createdAt,
+    );
+  }
+}

lib/features/notifications/data/notification_repository.dart

@@ -0,0 +1,103 @@
+import 'package:dio/dio.dart';
+import 'package:real_estate_mobile/core/network/api_client.dart';
+import 'package:real_estate_mobile/core/network/api_exceptions.dart';
+import 'package:real_estate_mobile/features/notifications/data/models/notification_model.dart';
+
+class NotificationRepository {
+  final Dio _dio = ApiClient.instance.dio;
+
+  /// Fetch notifications with optional filter and pagination.
+  /// GET /notifications?filter=all|unread&page=1&limit=20
+  Future<NotificationsResponse> getNotifications({
+    String filter = 'all',
+    int page = 1,
+    int limit = 20,
+  }) async {
+    try {
+      final response = await _dio.get('/notifications', queryParameters: {
+        'filter': filter,
+        'page': page,
+        'limit': limit,
+      });
+      final data = response.data['data'] as Map<String, dynamic>;
+      return NotificationsResponse.fromJson(data);
+    } on DioException catch (e) {
+      if (e.error is ApiException) throw e.error as ApiException;
+      throw ApiException(
+        message: e.message ?? 'Failed to fetch notifications',
+        statusCode: e.response?.statusCode,
+      );
+    }
+  }
+
+  /// Get unread notification count.
+  /// GET /notifications/unread-count
+  Future<int> getUnreadCount() async {
+    try {
+      final response = await _dio.get('/notifications/unread-count');
+      final data = response.data['data'] as Map<String, dynamic>;
+      return data['unreadCount'] as int? ?? 0;
+    } on DioException catch (e) {
+      if (e.error is ApiException) throw e.error as ApiException;
+      throw ApiException(
+        message: e.message ?? 'Failed to fetch unread count',
+        statusCode: e.response?.statusCode,
+      );
+    }
+  }
+
+  /// Mark a single notification as read.
+  /// PATCH /notifications/:id/read
+  Future<void> markAsRead(String notificationId) async {
+    try {
+      await _dio.patch('/notifications/$notificationId/read');
+    } on DioException catch (e) {
+      if (e.error is ApiException) throw e.error as ApiException;
+      throw ApiException(
+        message: e.message ?? 'Failed to mark notification as read',
+        statusCode: e.response?.statusCode,
+      );
+    }
+  }
+
+  /// Mark all notifications as read.
+  /// PATCH /notifications/read-all
+  Future<void> markAllAsRead() async {
+    try {
+      await _dio.patch('/notifications/read-all');
+    } on DioException catch (e) {
+      if (e.error is ApiException) throw e.error as ApiException;
+      throw ApiException(
+        message: e.message ?? 'Failed to mark all as read',
+        statusCode: e.response?.statusCode,
+      );
+    }
+  }
+}
+
+class NotificationsResponse {
+  final List<AppNotification> notifications;
+  final int unreadCount;
+  final int totalPages;
+  final int currentPage;
+
+  const NotificationsResponse({
+    required this.notifications,
+    required this.unreadCount,
+    required this.totalPages,
+    required this.currentPage,
+  });
+
+  factory NotificationsResponse.fromJson(Map<String, dynamic> json) {
+    final list = (json['notifications'] as List<dynamic>?)
+            ?.map((e) => AppNotification.fromJson(e as Map<String, dynamic>))
+            .toList() ??
+        [];
+    return NotificationsResponse(
+      notifications: list,
+      unreadCount: json['unreadCount'] as int? ?? 0,
+      totalPages: json['totalPages'] as int? ?? 1,
+      currentPage: json['currentPage'] as int? ?? 1,
+    );
+  }
+}