refactor: response api changed

docs/RESPONSE.md

@@ -19,4 +19,4 @@
 
 ```
 
-### Flutter
\ No newline at end of file
+### Flutter

lib/fluwx.dart

@@ -7,3 +7,4 @@ export 'src/wechat_reponse.dart';
 export 'src/wechat_scene.dart';
 export 'src/models/wechat_pay_model.dart';
 export 'src/models/wechat_send_auth_model.dart';
+export 'src/models/wechat_response.dart';