feat: K8s 集群同步功能 + 表单简化

- 新增手动同步按钮（卡片下拉菜单「同步」）
- 新建集群后自动触发同步（延迟500ms等列表刷新）
- 同步后刷新集群列表，节点/Pod/Deployment 数据写入 DB
- 集群表单：名称即code，正则校验英文/数字/连字符

frontend/src/components/kubernetes/KubernetesClusters.tsx

@@ -29,6 +29,7 @@ import {
   Container,
 } from 'lucide-react';
 import { kubernetesApi } from '@/services/api';
+import { toast } from 'sonner';
 import type { KubernetesCluster } from '@/types';
 import { KubernetesClusterDetail } from './KubernetesClusterDetail';
 import { KubernetesClusterDialog } from './KubernetesClusterDialog';
@@ -65,6 +66,24 @@ export function KubernetesClusters() {
     loadData();
   }, []);
 
+  // 新建后自动同步
+  const [pendingSyncId, setPendingSyncId] = useState<number | null>(null);
+
+  const handleSaved = () => {
+    loadData().then(() => {
+      if (!editingCluster) {
+        // 新建集群后，等列表刷新完再取最新一条同步
+        setTimeout(async () => {
+          const res: any = await kubernetesApi.getClusters();
+          const list = res?.list || [];
+          if (list.length > 0) {
+            handleSync(list[list.length - 1].id, true);
+          }
+        }, 500);
+      }
+    });
+  };
+
   const handleDelete = async (id: string) => {
     try {
       await kubernetesApi.deleteCluster(id);
@@ -74,6 +93,17 @@ export function KubernetesClusters() {
     }
   };
 
+  const handleSync = async (id: number | string, silent?: boolean) => {
+    try {
+      if (!silent) toast.info('正在同步集群资源...');
+      const res: any = await kubernetesApi.syncCluster(id);
+      if (!silent) toast.success(res?.message || '同步完成');
+      loadData();
+    } catch (e: any) {
+      if (!silent) toast.error(e?.message || '同步失败');
+    }
+  };
+
   const filteredClusters = clusters.filter(
     (cluster) =>
       (cluster.name || '').toLowerCase().includes(searchQuery.toLowerCase()) ||
@@ -280,6 +310,16 @@ export function KubernetesClusters() {
                             <Settings className="h-4 w-4 mr-2" />
                             配置
                           </DropdownMenuItem>
+                          <DropdownMenuItem
+                            className="text-cyan-400 focus:bg-slate-700 focus:text-cyan-300"
+                            onClick={(e) => {
+                              e.stopPropagation();
+                              handleSync(cluster.id);
+                            }}
+                          >
+                            <RefreshCw className="h-4 w-4 mr-2" />
+                            同步
+                          </DropdownMenuItem>
                           <DropdownMenuItem
                             className="text-emerald-400 focus:bg-slate-700 focus:text-emerald-300"
                             onClick={(e) => {
@@ -377,7 +417,7 @@ export function KubernetesClusters() {
         open={dialogOpen}
         onOpenChange={setDialogOpen}
         editingCluster={editingCluster}
-        onSaved={loadData}
+        onSaved={handleSaved}
       />
 
       {/* kubectl 终端 */}