feat: 添加移动端适配和测试功能

refactor(layout): 优化页脚布局和备案信息展示
feat(constants): 添加ICP备案和公安备案信息
feat(header): 实现移动端加载时的骨架屏效果
style(globals): 调整文字颜色和添加移动端响应样式
feat(breadcrumb): 增加返回按钮和响应式优化
feat(e2e): 添加移动端测试工具和测试用例
docs: 添加页脚重设计文档

src/components/layout/header.tsx

@@ -290,9 +290,27 @@ function HeaderContent() {
   );
 }
 
+function HeaderFallback() {
+  return (
+    <header className="fixed top-0 left-0 right-0 z-50 bg-transparent">
+      <div className="container-wide">
+        <div className="flex items-center justify-between h-16">
+          <div className="h-8 w-8 bg-gray-200 animate-pulse rounded" />
+          <nav className="hidden md:flex items-center gap-1">
+            {[1, 2, 3, 4, 5].map((i) => (
+              <div key={i} className="h-6 w-16 bg-gray-200 animate-pulse rounded mx-1" />
+            ))}
+          </nav>
+          <div className="h-9 w-20 bg-gray-200 animate-pulse rounded" />
+        </div>
+      </div>
+    </header>
+  );
+}
+
 export function Header() {
   return (
-    <Suspense fallback={<div className="h-16" />}>
+    <Suspense fallback={<HeaderFallback />}>
       <HeaderContent />
     </Suspense>
   );