退款审核功能：待交接取消不再自动退款，改为客服审核后原路退回

- 租客在待交接状态取消订单不再自动退款，改为 refund_status=pending_review
- 新增退款审核页面 /admin/orders/refund-review，客服可逐个审核
- 新增 POST /refund/approve 通过退款、POST /refund/reject 驳回退款
- 新增 GET /orders/refund-pending 查询待审核退款订单列表
- 优化状态标签表述：已取消→租客已取消、已关闭→客服已关闭、异常→客服介入
- 新增 refund_status: pending_review 及其前端标签「待客服审核退款」
- AdminOrderDetailView 退款状态改用统一 refundStatusLabel

frontend/src/features/admin/views/AdminOrderDetailView.vue

@@ -28,6 +28,7 @@ import {
   disputeStatusLabel,
   handoffStatusLabel,
   orderStatusLabel,
+  refundStatusLabel,
   settlementStatusLabel,
 } from '@/shared/utils/statusLabels'
 import { formatDateTime } from '@/shared/utils/time'
@@ -293,16 +294,6 @@ async function confirmRefund() {
   await handleRefund()
 }
 
-function refundStatusLabel(status: string) {
-  const map: Record<string, string> = {
-    pending: '待退款',
-    refunding: '退款中',
-    refunded: '已退款',
-    failed: '退款失败',
-  }
-  return map[status] || status || '未退款'
-}
-
 function paymentStatusLabel(status: string) {
   const map: Record<string, string> = {
     created: '已创建',