feat(dashboard): Implement system health check and enhance UI for agent management

frontend/src/components/providers/QueryProvider.tsx

@@ -0,0 +1,27 @@
+"use client";
+
+import type { ReactNode } from "react";
+import { useState } from "react";
+
+import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
+
+export function QueryProvider({ children }: { children: ReactNode }) {
+  const [client] = useState(
+    () =>
+      new QueryClient({
+        defaultOptions: {
+          queries: {
+            staleTime: 15_000,
+            gcTime: 5 * 60 * 1000,
+            refetchOnWindowFocus: true,
+            retry: 1,
+          },
+          mutations: {
+            retry: 0,
+          },
+        },
+      })
+  );
+
+  return <QueryClientProvider client={client}>{children}</QueryClientProvider>;
+}