feat: Implement support chat functionality, add 2FA verification screen and routing, and update dependencies.

lib/features/auth/data/auth_repository.dart

@@ -52,6 +52,58 @@ class AuthRepository {
     }
   }
 
+  /// Verify 2FA TOTP token during login
+  Future<AuthResponse> verifyTwoFactor({
+    required String tempToken,
+    required String token,
+  }) async {
+    try {
+      final response = await _dio.post(
+        ApiConstants.twoFactorVerify,
+        data: {'tempToken': tempToken, 'token': token},
+      );
+      final data = response.data['data'] as Map<String, dynamic>;
+      final authResponse = AuthResponse.fromJson(data);
+      await SecureStorage.saveTokens(
+        accessToken: authResponse.accessToken,
+        refreshToken: authResponse.refreshToken,
+      );
+      return authResponse;
+    } on DioException catch (e) {
+      if (e.error is ApiException) throw e.error as ApiException;
+      throw ApiException(
+        message: e.message ?? '2FA verification failed',
+        statusCode: e.response?.statusCode,
+      );
+    }
+  }
+
+  /// Verify backup code during login
+  Future<AuthResponse> verifyBackupCode({
+    required String tempToken,
+    required String backupCode,
+  }) async {
+    try {
+      final response = await _dio.post(
+        ApiConstants.twoFactorVerifyBackup,
+        data: {'tempToken': tempToken, 'backupCode': backupCode},
+      );
+      final data = response.data['data'] as Map<String, dynamic>;
+      final authResponse = AuthResponse.fromJson(data);
+      await SecureStorage.saveTokens(
+        accessToken: authResponse.accessToken,
+        refreshToken: authResponse.refreshToken,
+      );
+      return authResponse;
+    } on DioException catch (e) {
+      if (e.error is ApiException) throw e.error as ApiException;
+      throw ApiException(
+        message: e.message ?? 'Backup code verification failed',
+        statusCode: e.response?.statusCode,
+      );
+    }
+  }
+
   Future<UserModel> getMe() async {
     try {
       final response = await _dio.get(ApiConstants.authMe);