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/orders/api/orders.ts

@@ -34,6 +34,8 @@ export interface Order {
   status: OrderStatus
   handoff_status: HandoffStatus
   settlement_status: SettlementStatus
+  refund_status?: string
+  refund_amount_cent?: number
   active_dispute?: ActiveDispute
   checkout?: Checkout
   admin_actions?: AdminActions
@@ -364,3 +366,24 @@ export async function adminRefundOrder(id: number) {
   const { data } = await apiClient.post<ApiResponse<RefundStatus>>(`/admin/orders/${id}/refund`)
   return data.data
 }
+
+export async function adminApproveRefund(id: number) {
+  const { data } = await apiClient.post<ApiResponse<{ approved: boolean }>>(
+    `/admin/orders/${id}/refund/approve`
+  )
+  return data.data
+}
+
+export async function adminRejectRefund(id: number) {
+  const { data } = await apiClient.post<ApiResponse<{ rejected: boolean }>>(
+    `/admin/orders/${id}/refund/reject`
+  )
+  return data.data
+}
+
+export async function fetchPendingRefundOrders() {
+  const { data } = await apiClient.get<ApiResponse<{ items: Order[] }>>(
+    '/admin/orders/refund-pending'
+  )
+  return data.data.items
+}