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

lib/core/constants/api_constants.dart

@@ -31,4 +31,11 @@ class ApiConstants {
   // Messages
   static const String conversations = '/messages/conversations';
   static const String unreadCount = '/messages/unread-count';
+
+  // Support Chat
+  static const String supportChat = '/support-chat';
+
+  // 2FA
+  static const String twoFactorVerify = '/auth/2fa/verify';
+  static const String twoFactorVerifyBackup = '/auth/2fa/verify-backup';
 }