feat: flutter ui integration

ui/flutter/lib/api/model/result.dart

@@ -0,0 +1,26 @@
+import 'package:json_annotation/json_annotation.dart';
+
+part 'result.g.dart';
+
+@JsonSerializable(genericArgumentFactories: true)
+class Result<T> {
+  String? msg;
+  T? data;
+
+  Result({
+    this.msg,
+    this.data,
+  });
+
+  factory Result.fromJson(
+    Map<String, dynamic> json,
+    T Function(dynamic json) fromJsonT,
+  ) =>
+      _$ResultFromJson(json, fromJsonT);
+  Map<String, dynamic> toJson() => {
+        'msg': msg,
+        'data': data is List
+            ? (data as dynamic)?.map((e) => e.toJson()).toList()
+            : (data as dynamic)?.toJson(),
+      };
+}