feat: 实时消息与管理端运营能力

新增群聊/私信与公共 WebSocket 总线，站长用户内容档案，并将通知与待审角标改为推送驱动；同步精简管理仪表盘并修复主题换肤 DOM 冲突。

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

frontend/app/admin/AdminNav.tsx

@@ -21,6 +21,7 @@ import {
   isSuperOrOwner,
   type RoleUserLike,
 } from "@/lib/roles";
+import { realtime, RT_MODERATION_CHANGED } from "@/lib/realtime";
 import Avatar from "@/components/Avatar";
 import RoleBadge from "@/components/RoleBadge";
 
@@ -69,7 +70,7 @@ function isActive(pathname: string, href: string, exact?: boolean) {
   return exact ? pathname === href : pathname === href || pathname.startsWith(`${href}/`);
 }
 
-/** 待审核数量轮询（30 秒）；仅内容审核入口可见时启用 */
+/** 待审核数量：首屏 + WS 推送 + 回前台校准（无定时轮询） */
 function usePendingCounts(enabled: boolean) {
   const [counts, setCounts] = useState({ posts: 0, comments: 0 });
   useEffect(() => {
@@ -83,14 +84,14 @@ function usePendingCounts(enabled: boolean) {
         .catch(() => {});
     };
     load();
-    const t = setInterval(load, 30_000);
+    const off = realtime.on(RT_MODERATION_CHANGED, () => load());
     const onVisible = () => {
       if (document.visibilityState === "visible") load();
     };
     document.addEventListener("visibilitychange", onVisible);
     return () => {
       alive = false;
-      clearInterval(t);
+      off();
       document.removeEventListener("visibilitychange", onVisible);
     };
   }, [enabled]);