fix: some problems are fixed

lib/core/storage/token_storage.dart

@@ -1,8 +1,9 @@
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 
-/// ذخیره‌ی امن توکن JWT.
+/// ذخیره‌ی امن توکن JWT و شماره‌ی موبایلِ کاربر.
 class TokenStorage {
   static const _key = 'jwt_token';
+  static const _mobileKey = 'user_mobile';
   final FlutterSecureStorage _storage;
 
   TokenStorage([FlutterSecureStorage? storage])
@@ -12,5 +13,13 @@ class TokenStorage {
 
   Future<void> write(String token) => _storage.write(key: _key, value: token);
 
-  Future<void> clear() => _storage.delete(key: _key);
+  Future<String?> readMobile() => _storage.read(key: _mobileKey);
+
+  Future<void> writeMobile(String mobile) =>
+      _storage.write(key: _mobileKey, value: mobile);
+
+  Future<void> clear() async {
+    await _storage.delete(key: _key);
+    await _storage.delete(key: _mobileKey);
+  }
 }