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/risk_widgets_test.dart

@@ -0,0 +1,92 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:ichino/config/strings.dart';
+import 'package:ichino/widgets/risk/risk_list_widgets.dart';
+
+Widget _wrap(Widget child) =>
+    MaterialApp(home: Scaffold(body: Column(children: [child])));
+
+void main() {
+  testWidgets('RiskPendingList 空列表显示提示，非空显示行', (tester) async {
+    await tester.pumpWidget(
+      _wrap(
+        const RiskPendingList(
+          title: '待解锁',
+          emptyHint: '还没有添加',
+          count: 0,
+          rows: [],
+        ),
+      ),
+    );
+    expect(find.text('待解锁 (0)'), findsOneWidget);
+    expect(find.text('还没有添加'), findsOneWidget);
+
+    await tester.pumpWidget(
+      _wrap(
+        RiskPendingList(
+          title: '待解锁',
+          emptyHint: '还没有添加',
+          count: 1,
+          rows: const [
+            RiskPendingRow(leading: '#834', trailing: 'Master', onRemove: _noop),
+          ],
+        ),
+      ),
+    );
+    expect(find.text('待解锁 (1)'), findsOneWidget);
+    expect(find.text('还没有添加'), findsNothing);
+    expect(find.textContaining('#834'), findsOneWidget);
+  });
+
+  testWidgets('RiskPendingRow 禁用时删除按钮不触发回调', (tester) async {
+    var removed = 0;
+    await tester.pumpWidget(
+      _wrap(
+        RiskPendingRow(
+          leading: '#1',
+          trailing: 'x',
+          onRemove: () => removed++,
+          enabled: false,
+        ),
+      ),
+    );
+    final button = tester.widget<IconButton>(find.byType(IconButton));
+    expect(button.onPressed, isNull);
+    expect(find.byTooltip(AppStrings.listRemoveTooltip), findsOneWidget);
+
+    await tester.pumpWidget(
+      _wrap(
+        RiskPendingRow(
+          leading: '#1',
+          trailing: 'x',
+          onRemove: () => removed++,
+        ),
+      ),
+    );
+    await tester.tap(find.byTooltip(AppStrings.listRemoveTooltip));
+    expect(removed, 1);
+  });
+
+  testWidgets('RiskNumberField 与 RiskAddButton 共用统一样式', (tester) async {
+    final controller = TextEditingController();
+    addTearDown(controller.dispose);
+    var added = 0;
+
+    await tester.pumpWidget(
+      _wrap(
+        Column(
+          children: [
+            RiskNumberField(controller: controller, label: 'A', hint: 'B'),
+            RiskAddButton(onPressed: () => added++),
+          ],
+        ),
+      ),
+    );
+    expect(find.text('A'), findsOneWidget);
+    expect(find.text('B'), findsOneWidget);
+    await tester.tap(find.text(AppStrings.listAddButton));
+    expect(added, 1);
+  });
+}
+
+void _noop() {}