feat(finance): P2 手动退款登记与成本异常闭环

- 迁移 112：order_refunds（订单项级退款，整单拆多条共享 batch_no，source/external_ref 预留平台 API）+ cost_exceptions.resolution_note
- 新服务 order-refund-service：整单/指定商品退款、可退金额校验、撤销、全额退完同步 pay_status
- 销售事实改为按有效退款记录冲减；无记录时仍兼容 pay_status=refunded 的历史全额退款
- 订单详情新增退款登记与退款记录表，商品明细显示收入/已退/可退
- 全额退款自动关闭该订单项成本异常并写处理备注；成本异常处理改为带备注弹窗
- 财务事件 UNION 接入退款记录，文档同步 P2 状态与 API

apps/frontend/src/services/admin/orders.ts

@@ -1,5 +1,10 @@
 import { apiGet, apiPost } from '@/lib/http'
-import type { AdminOrderDetail, AdminOrderListItem, AdminPagination } from '@/types/admin'
+import type {
+  AdminOrderDetail,
+  AdminOrderListItem,
+  AdminOrderRefund,
+  AdminPagination,
+} from '@/types/admin'
 
 export function fetchAdminOrders(params?: Record<string, unknown>) {
   return apiGet<{ items: AdminOrderListItem[]; pagination: AdminPagination }>(
@@ -24,3 +29,32 @@ export function updateAdminOrderClaimStatus(
     claimStatusUpdatedAt: string
   }>(`/api/v1/admin/orders/${orderId}/claim-status`, payload)
 }
+
+export function createAdminOrderRefund(
+  orderId: number | string,
+  payload: {
+    orderItemId?: number
+    amountFen?: number
+    reason?: string
+    note?: string
+    refundedAt?: string
+  },
+) {
+  return apiPost<{
+    batchNo: string
+    refunds: AdminOrderRefund[]
+    fullRefunded: boolean
+    closedExceptionCount: number
+  }>(`/api/v1/admin/orders/${orderId}/refunds`, payload)
+}
+
+export function voidAdminOrderRefund(
+  orderId: number | string,
+  refundId: number,
+  payload: { reason?: string },
+) {
+  return apiPost<{ refund: AdminOrderRefund; rebuiltDate: string }>(
+    `/api/v1/admin/orders/${orderId}/refunds/${refundId}/void`,
+    payload,
+  )
+}