perf(frontend,config): parallelize auth, virtualize logs, cache public configs

Frontend layout renders immediately; pages gate via RequireAuth and
useAuthRedirect. Login/register skip getUserInfo. Admin log panel uses
useVirtualizer to avoid 2000-row DOM. ListVisibleSystemConfigs caches
visibility=1 configs in Redis with invalidation on create/update.
PERFORMANCE.md marks completed optimizations.

frontend/components/auth/require-auth.tsx

@@ -0,0 +1,67 @@
+"use client"
+
+import type {ReactNode} from "react"
+import {Loader2} from "lucide-react"
+
+import {ErrorPage} from "@/components/layout/error"
+import {useUser} from "@/contexts/user-context"
+
+type RequireAuthProps = {
+  children: ReactNode
+  fallback?: ReactNode
+  minHeightClassName?: string
+}
+
+/**
+ * Guards page content until the session user is available.
+ * Redirect to login is handled by the parent layout; this only covers the content slot.
+ */
+export function RequireAuth({
+  children,
+  fallback,
+  minHeightClassName = "min-h-[400px]",
+}: RequireAuthProps) {
+  const {user, loading} = useUser()
+
+  if (loading) {
+    return fallback ?? (
+      <div className={`flex items-center justify-center ${minHeightClassName}`}>
+        <Loader2 className="size-6 animate-spin text-primary" />
+      </div>
+    )
+  }
+
+  if (!user) {
+    return null
+  }
+
+  return <>{children}</>
+}
+
+type RequireAdminAuthProps = {
+  children: ReactNode
+}
+
+/** Guards admin routes after the shared shell has rendered. */
+export function RequireAdminAuth({children}: RequireAdminAuthProps) {
+  const {user, loading} = useUser()
+
+  if (loading) {
+    return (
+      <div className="flex min-h-[400px] items-center justify-center">
+        <Loader2 className="size-6 animate-spin text-primary" />
+      </div>
+    )
+  }
+
+  if (!user?.is_admin) {
+    return (
+      <ErrorPage
+        title="访问被拒绝"
+        message="您没有权限访问此页面"
+      />
+    )
+  }
+
+  return <>{children}</>
+}