fix(web): recover vehicle option lookups

vehicle-data-platform/apps/web/src/v2/pages/TrackPage.tsx

@@ -113,11 +113,12 @@ function VehiclePicker({ value, onChange, onSelect }: { value: string; onChange:
     {open ? <div className="v2-track-vehicle-options" role="listbox">
       <header><span>车辆候选</span><em>支持车牌或 VIN</em></header>
       {candidates.isFetching ? <p><span className="v2-spinner" />正在搜索车辆</p> : null}
+      {!candidates.isFetching && candidates.isError ? <div className="v2-vehicle-option-error" role="alert"><span>{candidates.error instanceof Error ? candidates.error.message : '车辆候选加载失败'}</span><button type="button" onMouseDown={(event) => event.preventDefault()} onClick={() => void candidates.refetch()}>重试</button></div> : null}
       {!candidates.isFetching && (candidates.data?.items ?? []).map((vehicle) => <button
         type="button" role="option" aria-selected={false} key={vehicle.vin}
         onMouseDown={(event) => event.preventDefault()} onClick={() => { onSelect(vehicle); setOpen(false); }}
       ><strong>{vehicle.plate || '未绑定车牌'}</strong><span>{vehicle.vin}</span><em>选择</em></button>)}
-      {!candidates.isFetching && !(candidates.data?.items.length) ? <p>没有匹配车辆</p> : null}
+      {!candidates.isFetching && !candidates.isError && !(candidates.data?.items.length) ? <p>没有匹配车辆</p> : null}
     </div> : null}
   </div>;
 }