feat(web): 定时拉取优化——静默刷新不闪loading + AdminTable稳定排序/键控不重排

- useAsyncData: dataRef跟踪,首次setLoading(骨架),已有data时不设loading(静默后台拉),成功setData/失败保留旧data
- AdminTable: rows 按 rowKey 升序稳定排序(useMemo,同批数据顺序稳定不跳),稳定key diff复用DOM不整页重绘,error&&!hasRows才显示错误(保留旧表)
- 受益: 所有useAsyncData/AdminTable面板页(会话/记忆/渠道/IoT/插件/人格/用户/RAG/LLM/自动化/可观测/仪表盘)
- npm run build绿(83模块)

frontend/web/src/lib/useAsyncData.ts

@@ -8,18 +8,26 @@ interface AsyncState<T> {
 }
 
 /** Runs an async factory on mount (and on reload), tracking loading/error so
- *  every API-backed surface has a complete state. Best-effort, no `any`. */
+ *  every API-backed surface has a complete state. Best-effort, no `any`.
+ *
+ *  Reloads after the first load are *silent*: once data is on screen the old
+ *  list is kept (no loading flicker) and only replaced when fresh data lands.
+ *  If a silent refresh fails, the old data is preserved and the error recorded
+ *  for the next state read. The first (data-less) load still shows loading. */
 export function useAsyncData<T>(fn: () => Promise<T>, deps: readonly unknown[] = []): AsyncState<T> {
   const [data, setData] = useState<T | null>(null);
   const [loading, setLoading] = useState(true);
   const [error, setError] = useState<string | null>(null);
+  const dataRef = useRef<T | null>(null);
+  dataRef.current = data;
   const fnRef = useRef(fn);
   fnRef.current = fn;
   const depsKey = deps.join("\u0000");
 
   const run = useCallback(() => {
     let cancelled = false;
-    setLoading(true);
+    const first = dataRef.current == null;
+    if (first) setLoading(true);
     setError(null);
     fnRef
       .current()
@@ -30,7 +38,7 @@ export function useAsyncData<T>(fn: () => Promise<T>, deps: readonly unknown[] =
         if (!cancelled) setError(err instanceof Error ? err.message : "加载失败");
       })
       .finally(() => {
-        if (!cancelled) setLoading(false);
+        if (!cancelled && first) setLoading(false);
       });
     return () => {
       cancelled = true;