update api

lib/features/auth/data/models/register_dto.dart

@@ -0,0 +1,24 @@
+/// Register request Data Transfer Object
+class RegisterDto {
+  final String name;
+  final String email;
+  final String password;
+  final List<String> roles;
+
+  const RegisterDto({
+    required this.name,
+    required this.email,
+    required this.password,
+    this.roles = const ['user'],
+  });
+
+  /// Convert to JSON for API request
+  Map<String, dynamic> toJson() {
+    return {
+      'name': name,
+      'email': email,
+      'password': password,
+      'roles': roles,
+    };
+  }
+}