fix: 修复开发模式下，首页请求两次的问题

src/pages/dashboard/Dashboard.jsx

@@ -21,13 +21,20 @@ const Dashboard = () => {
   const [pushForm] = Form.useForm();
   const [messageApi, contextHolder] = message.useMessage();
   
+  // 添加ref来避免在开发模式下的重复API请求
+  const fetchingRef = React.useRef(false);
+
   useEffect(() => {
+    if (!fetchingRef.current) {
+      fetchingRef.current = true;
       dispatch(fetchFuturesOverview());
       dispatch(fetchRiskAlerts());
       dispatch(fetchAIMarketAnalysis());
+    }
   }, [dispatch]);
 
   const handleRefresh = () => {
+    fetchingRef.current = false;
     dispatch(fetchFuturesOverview());
     dispatch(fetchRiskAlerts());
     dispatch(fetchAIMarketAnalysis());