feat: 扫码页支持URL参数自动查询 — /scan?sn=xxx 直接展示流转树

frontend/src/pages/ScanPage.tsx

@@ -1,5 +1,6 @@
 /** 扫码干活页 — 编排摄像头扫码 + 手动输入 + 查询结果 */
-import { useState, useCallback, Suspense, lazy } from "react";
+import { useState, useCallback, useEffect, Suspense, lazy } from "react";
+import { useSearchParams } from "react-router-dom";
 import { QrCode, Loader2 } from "lucide-react";
 import { scanProduct } from "../services/productApi";
 import type { ProductScanResponse } from "../types/api";
@@ -10,6 +11,7 @@ import QueryResult from "../components/scan/QueryResult";
 const CameraScanner = lazy(() => import("../components/scan/CameraScanner"));
 
 export default function ScanPage() {
+  const [searchParams] = useSearchParams();
   const [cameraActive, setCameraActive] = useState(false);
   const [cameraError, setCameraError] = useState<string | null>(null);
   const [serialNumber, setSerialNumber] = useState("");
@@ -39,6 +41,12 @@ export default function ScanPage() {
     }
   }, []);
 
+  // URL 参数自动查询（支持从看板等外部跳转）
+  useEffect(() => {
+    const sn = searchParams.get("sn");
+    if (sn) doQuery(sn.trim());
+  }, [searchParams, doQuery]);
+
   /** 扫码回调：提取纯产品身份证 */
   const handleScan = useCallback(
     (decodedText: string) => {