refactor: 拆分主页与公共组件，扫码登录改走 WinHTTP

- 抽出 lib/core 的日期/JSON 工具，收敛各页重复解析
- 主页与音乐风险页拆成组件，风险功能共用一套运行框架
- 修复设置页作为主页页签保存时弹掉根路由导致的黑屏
- 登录对齐 Astral aimedb 协议：84 位二维码校验、签名与请求头修正，
  补 GlobalSign 中间证书；Windows 改用 WinHTTP 绕过服务端对
  BoringSSL 的 TLS 指纹拦截（证书校验保持开启）
- 补开发预览数据与测试

test/qr_login_test.dart

@@ -0,0 +1,88 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:ichino/config/title_server_config.dart';
+import 'package:ichino/services/api_service.dart';
+
+/// 扫码登录的输入归一化与 Keychip 拼装：纯逻辑，不发请求。
+void main() {
+  const payload = 'A63E01C304710072610022219460000000000000000000000000000000000000';
+  const qrString = 'SGWCMAID261002221946$payload';
+  const qrUrl =
+      'https://wq.wahlap.net/qrcode/req/MAID261002221946$payload.html'
+      '?l=123456&t=261002221946&d=1';
+
+  group('normalizeQr / extractQRCode', () {
+    test('84 位二维码串取后 64 位载荷', () {
+      expect(payload.length, 64);
+      expect(qrString.length, 84);
+      expect(ApiService.extractQRCode(qrString), payload);
+    });
+
+    test('二维码链接还原成同一条串', () {
+      expect(ApiService.normalizeQr(qrUrl), qrString);
+      expect(ApiService.extractQRCode(qrUrl), payload);
+    });
+
+    test('长度、前缀、GameID、载荷字符集不合预期时抛 FormatException', () {
+      expect(
+        () => ApiService.normalizeQr('ABCDEF' * 12),
+        throwsFormatException,
+      );
+      expect(
+        () => ApiService.normalizeQr('XGWC${qrString.substring(4)}'),
+        throwsFormatException,
+      );
+      expect(
+        () => ApiService.normalizeQr('SGWCXBID${qrString.substring(8)}'),
+        throwsFormatException,
+      );
+      expect(
+        () => ApiService.normalizeQr('SGWCMAID261002221946${'G' * 64}'),
+        throwsFormatException,
+      );
+      expect(
+        () => ApiService.normalizeQr('https://wq.wahlap.net/other/x.html'),
+        throwsFormatException,
+      );
+    });
+  });
+
+  group('formatTimestamp', () {
+    test('本机本地墙上时间，yymmddHHMMss', () {
+      expect(
+        ApiService.formatTimestamp(DateTime(2026, 10, 2, 22, 19, 46)),
+        '261002221946',
+      );
+      expect(
+        ApiService.formatTimestamp(DateTime(2026, 1, 5, 7, 3, 9)),
+        '260105070309',
+      );
+    });
+  });
+
+  group('TitleServerConfig.fullKeychipId', () {
+    TitleServerConfig config(String keychip, {int placeId = 1007}) =>
+        TitleServerConfig(
+          titleServerUrl: 'https://example.invalid',
+          aesKey: 'k',
+          aesIv: 'v',
+          clientId: 'A63E01C3047',
+          placeId: placeId,
+          keychipId: keychip,
+        );
+
+    test('完整形式（带连字符 / 连写 / 小写）归一到大写带连字符', () {
+      expect(config('A63E-01C30471007').fullKeychipId, 'A63E-01C30471007');
+      expect(config('A63E01C30471007').fullKeychipId, 'A63E-01C30471007');
+      expect(config('a63e-01c30471007').fullKeychipId, 'A63E-01C30471007');
+    });
+
+    test('只填 11 位短值时按 placeId 补全', () {
+      expect(config('A63E01C3047').fullKeychipId, 'A63E-01C30471007');
+    });
+
+    test('短于 11 位当没配，交给登录层报错', () {
+      expect(config('').fullKeychipId, isEmpty);
+      expect(config('A63E01').fullKeychipId, isEmpty);
+    });
+  });
+}