fix: address review issues in brand filter sync, model guard, route counts, and candidate loading

- Sync blockedBrands local state after save to prevent stale chips
- Defer getBrandList from blocking Settings bootstrap
- Guard model management UI on brandGroups instead of availableModels
- Deduplicate single-model add in disabled models
- Skip read-only/zero-channel routes in enabledCounts and filter
- Add sequence counter to loadCandidates to prevent force race condition
- Use stableAddChannel for mobile add-channel button

src/web/pages/Settings.tsx

@@ -424,14 +424,6 @@ export default function Settings() {
         api.getRoutesLite(),
         api.getRuntimeDatabaseConfig(),
       ]);
-      let brandListBrands: string[] = [];
-      try {
-        const brandListRes = await api.getBrandList();
-        brandListBrands = Array.isArray(brandListRes?.brands) ? brandListRes.brands : [];
-      } catch {
-        // best-effort: brand list is non-critical
-      }
-      setAllBrandNames(brandListBrands);
       setMaskedToken(authInfo.masked || '****');
       setRuntime({
         checkinCron: runtimeInfo.checkinCron || '0 8 * * *',
@@ -508,6 +500,10 @@ export default function Settings() {
     } finally {
       setLoading(false);
     }
+    // Load brand list in background (non-blocking, best-effort)
+    api.getBrandList()
+      .then((res: any) => setAllBrandNames(Array.isArray(res?.brands) ? res.brands : []))
+      .catch(() => {/* best-effort */});
   };
 
   useEffect(() => {
@@ -834,10 +830,9 @@ export default function Settings() {
     setSavingBrandFilter(true);
     try {
       const res = await api.updateRuntimeSettings({ globalBlockedBrands: blockedBrands });
-      setRuntime((prev) => ({
-        ...prev,
-        globalBlockedBrands: Array.isArray(res?.globalBlockedBrands) ? res.globalBlockedBrands : blockedBrands,
-      }));
+      const resolved = Array.isArray(res?.globalBlockedBrands) ? res.globalBlockedBrands : blockedBrands;
+      setRuntime((prev) => ({ ...prev, globalBlockedBrands: resolved }));
+      setBlockedBrands(resolved);
       toast.success('品牌屏蔽设置已保存');
       try {
         await api.rebuildRoutes(false);

src/web/pages/Sites.tsx

@@ -953,7 +953,7 @@ export default function Sites() {
                 ) : (
                   <>
                     {/* Search and brand group controls */}
-                    {availableModels.length > 0 && (
+                    {brandGroups.length > 0 && (
                       <div style={{ marginBottom: 10 }}>
                         <input
                           placeholder="搜索模型名称..."
@@ -1016,7 +1016,7 @@ export default function Sites() {
                                       checked={isDisabled}
                                       onChange={(e) => {
                                         if (e.target.checked) {
-                                          setDisabledModels((prev) => [...prev, model]);
+                                          setDisabledModels((prev) => Array.from(new Set([...prev, model])));
                                         } else {
                                           setDisabledModels((prev) => prev.filter((m) => m !== model));
                                         }

src/web/pages/TokenRoutes.tsx

@@ -164,6 +164,7 @@ export default function TokenRoutes() {
   const candidatesLoadedRef = useRef(false);
   const candidatesPromiseRef = useRef<Promise<void> | null>(null);
   const candidatesVersionRef = useRef(0);
+  const candidatesSeqRef = useRef(0);
 
   const loadRouteDecisions = async (
     routeRows: RouteSummaryRow[],
@@ -235,10 +236,12 @@ export default function TokenRoutes() {
   const loadCandidates = (force?: boolean) => {
     if (candidatesLoadedRef.current && !force) return;
     if (candidatesPromiseRef.current && !force) return;
+    const seq = ++candidatesSeqRef.current;
     candidatesLoadedRef.current = true;
     const promise = (async () => {
       try {
         const candidateRows = await api.getModelTokenCandidates();
+        if (candidatesSeqRef.current !== seq) return; // stale
         startTransition(() => {
           setModelCandidates((candidateRows?.models || {}) as RouteModelCandidatesByModelName);
           setMissingTokenModelsByName(
@@ -251,7 +254,7 @@ export default function TokenRoutes() {
         });
         candidatesVersionRef.current = Date.now();
       } catch {
-        candidatesLoadedRef.current = false;
+        if (candidatesSeqRef.current === seq) candidatesLoadedRef.current = false;
       } finally {
         if (candidatesPromiseRef.current === promise) {
           candidatesPromiseRef.current = null;
@@ -740,6 +743,7 @@ export default function TokenRoutes() {
     let enabled = 0;
     let disabled = 0;
     for (const route of baseFilteredRoutes) {
+      if (route.kind === 'zero_channel' || route.readOnly === true || route.isVirtual === true) continue;
       if (route.enabled) enabled++;
       else disabled++;
     }
@@ -748,8 +752,10 @@ export default function TokenRoutes() {
 
   const filteredRoutes = useMemo(() => {
     if (enabledFilter === 'all') return baseFilteredRoutes;
-    if (enabledFilter === 'enabled') return baseFilteredRoutes.filter((route) => route.enabled);
-    return baseFilteredRoutes.filter((route) => !route.enabled);
+    return baseFilteredRoutes.filter((route) => {
+      if (route.kind === 'zero_channel' || route.readOnly === true || route.isVirtual === true) return false;
+      return enabledFilter === 'enabled' ? route.enabled : !route.enabled;
+    });
   }, [baseFilteredRoutes, enabledFilter]);
 
   useEffect(() => {
@@ -1451,7 +1457,7 @@ export default function TokenRoutes() {
                         <button
                           type="button"
                           className="btn btn-link"
-                          onClick={() => setAddChannelModalRouteId(route.id)}
+                          onClick={() => stableAddChannel(route.id)}
                         >
                           {tr('添加通道')}
                         </button>