add auth register

lib/features/auth/domain/entities/city.dart

@@ -0,0 +1,60 @@
+/// Domain Entity: City
+///
+/// Represents a city/province for address selection.
+library;
+
+/// City Entity
+class City {
+  /// Unique city identifier
+  final String name;
+
+  /// City code (e.g., "01", "02")
+  final String code;
+
+  /// Display name
+  final String cityName;
+
+  const City({
+    required this.name,
+    required this.code,
+    required this.cityName,
+  });
+
+  /// Create from JSON map
+  factory City.fromJson(Map<String, dynamic> json) {
+    return City(
+      name: json['name'] as String,
+      code: json['code'] as String,
+      cityName: json['city_name'] as String,
+    );
+  }
+
+  /// Convert to JSON map
+  Map<String, dynamic> toJson() {
+    return {
+      'name': name,
+      'code': code,
+      'city_name': cityName,
+    };
+  }
+
+  @override
+  bool operator ==(Object other) {
+    if (identical(this, other)) return true;
+
+    return other is City &&
+        other.name == name &&
+        other.code == code &&
+        other.cityName == cityName;
+  }
+
+  @override
+  int get hashCode {
+    return Object.hash(name, code, cityName);
+  }
+
+  @override
+  String toString() {
+    return 'City(name: $name, code: $code, cityName: $cityName)';
+  }
+}