fix(admin): 后台列表切换保留当前内容，去掉加载占位

用户档案、用户列表、内容筛选与公告页等数据到达后再换视图，避免滚动条闪动。

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/app/admin/users/[id]/page.tsx

@@ -1,7 +1,11 @@
 import type { Metadata } from "next";
 import { cookies } from "next/headers";
 import { authCookieHeader } from "@/lib/cookies";
-import { fetchAdminUserAudit } from "@/lib/api";
+import {
+  fetchAdminUserAudit,
+  fetchAdminUserAuditPosts,
+  type AdminAuditPostItem,
+} from "@/lib/api";
 import { getMeCached } from "@/lib/serverData";
 import { isOwner, isSuperOrOwner } from "@/lib/roles";
 import Forbidden from "../../Forbidden";
@@ -32,13 +36,38 @@ export default async function AdminUserAuditPage({ params }: PageProps) {
     return <Forbidden text="用户内容档案仅站长可查看。" />;
   }
 
-  let profile;
-  try {
-    profile = await fetchAdminUserAudit(userId, cookie || undefined);
-  } catch (e) {
-    const msg = e instanceof Error ? e.message : "获取用户档案失败";
-    return <Forbidden text={msg} />;
+  const cookieOrUndef = cookie || undefined;
+  const [profileSettled, postsSettled] = await Promise.all([
+    fetchAdminUserAudit(userId, cookieOrUndef)
+      .then((profile) => ({ ok: true as const, profile }))
+      .catch((e) => ({
+        ok: false as const,
+        error: e instanceof Error ? e.message : "获取用户档案失败",
+      })),
+    fetchAdminUserAuditPosts(userId, 1, cookieOrUndef)
+      .then((res) => ({ ok: true as const, res }))
+      .catch((e) => ({
+        ok: false as const,
+        error: e instanceof Error ? e.message : "获取帖子失败",
+      })),
+  ]);
+
+  if (!profileSettled.ok) {
+    return <Forbidden text={profileSettled.error} />;
   }
 
-  return <UserAuditClient userId={userId} initial={profile} />;
+  const initialPosts: AdminAuditPostItem[] = postsSettled.ok ? postsSettled.res.items || [] : [];
+  const initialPostsTotal = postsSettled.ok ? postsSettled.res.total : 0;
+  const initError = postsSettled.ok ? "" : postsSettled.error;
+  const profile = profileSettled.profile;
+
+  return (
+    <UserAuditClient
+      userId={userId}
+      initial={profile}
+      initialPosts={initialPosts}
+      initialPostsTotal={initialPostsTotal}
+      initError={initError}
+    />
+  );
 }