feat: 对齐常驻商城与七鱼客服交互

- 同步商城 H5 登录态与原生 token
- 完善商城/原生 tab 切换、动画及返回交互
- 修复七鱼客服键盘避让和状态栏恢复
- 调整开屏跳过按钮与登录入口交互

test/features/ads/proto_message_test.dart

@@ -0,0 +1,13 @@
+import 'dart:convert';
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:jinzhi_flutter_app/features/ads/data/ads_api_client.dart';
+
+void main() {
+  test('protobuf strings are decoded as UTF-8', () {
+    final value = utf8.encode('商城');
+    final message = ProtoMessage(<int>[10, value.length, ...value]);
+
+    expect(message.string(1), '商城');
+  });
+}