fix(web): recover vehicle option lookups

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

@@ -174,10 +174,11 @@ function VehicleMultiSelect({ value, onChange }: { value: VehicleOption[]; onCha
       {open ? <div className="v2-mileage-options" role="listbox">
         <header><span>车牌候选</span><em>{value.length}/{MAX_SELECTED_VEHICLES} 已选</em></header>
         {candidates.isLoading ? <p>正在搜索车辆…</p> : null}
+        {!candidates.isLoading && candidates.isError ? <div className="v2-vehicle-option-error" role="alert"><span>{candidates.error instanceof Error ? candidates.error.message : '车牌候选加载失败'}</span><button type="button" onMouseDown={(event) => event.preventDefault()} onClick={() => void candidates.refetch()}>重试</button></div> : null}
         {!candidates.isLoading && options.map((vehicle) => <button type="button" role="option" aria-selected={selected.has(vehicle.vin)} key={vehicle.vin} disabled={selected.has(vehicle.vin)} onMouseDown={(event) => event.preventDefault()} onClick={() => add(vehicle)}>
           <strong>{vehicle.plate || '未绑定车牌'}</strong><span>{vehicle.vin}</span>{selected.has(vehicle.vin) ? <em>已选择</em> : null}
         </button>)}
-        {!candidates.isLoading && !options.length ? <p>没有匹配的车牌</p> : null}
+        {!candidates.isLoading && !candidates.isError && !options.length ? <p>没有匹配的车牌</p> : null}
       </div> : null}
     </div>
     <small>支持车牌关键字搜索，最多选择 {MAX_SELECTED_VEHICLES} 辆</small>