优化开放 API 文档：创建订单响应示例补全为真实完整字段

- 响应示例从 4 个字段补全为完整订单对象（product/金额/手续费/时间等 21 字段）
- 备注补充双单号说明：下单后保存 order_no 用于后续链路，client_order_no 仅用于幂等
- 说明 data 透传字段行为

frontend/src/openapi/endpoints.ts

@@ -214,18 +214,34 @@ export const endpoints: EndpointSpec[] = [
       "order_no": "FO20260730000123",
       "client_order_no": "shop-10001",
       "order_status": "paid",
-      "can_ship": true
+      "can_ship": true,
+      "cannot_ship_reason": "",
+      "product": { "sku": "suit_pink_sheep", "name": "套装-糯粉咩咩" },
+      "quantity": 1,
+      "base_amount": 100,
+      "fee_type": "rate",
+      "service_fee_amount": 5,
+      "amount": 105,
+      "currency": "POINT",
+      "buyer_reference": "buyer-001",
+      "data": { "server": "ios-wechat", "uid": "player-id" },
+      "provider_order_no": "",
+      "failure_reason": "",
+      "created_at": "2026-07-30T10:00:00+08:00",
+      "delivered_at": null,
+      "cancelled_at": null
     }
   }
 }`,
     responseFields: [
-      { name: 'idempotent', type: 'bool', desc: 'true 表示该 client_order_no 已存在，返回既有订单' },
+      { name: 'idempotent', type: 'bool', desc: 'true 表示该 client_order_no 已存在，返回既有订单（未重复扣款）' },
-      { name: 'order', type: 'object', desc: '订单对象，字段见「订单字段说明」' },
+      { name: 'order', type: 'object', desc: '订单完整对象，字段见下方「订单字段说明」' },
     ],
     notes: [
-      'client_order_no 是唯一幂等单号，请保证同一商户下不重复。',
+      'client_order_no 是唯一幂等单号，请保证同一商户下不重复；重复请求不会重复扣款，返回 idempotent=true 及既有订单。',
       '当前无真实支付流程，下单成功即扣款并进入 order_status=paid，余额不足返回 400。',
-      '同一 client_order_no 重复请求不会重复扣款，返回 idempotent=true。',
+      '下单成功后请保存 order_no，后续查询/发货/回调均以 order_no 为准；client_order_no 仅用于幂等。',
+      'data 字段会原样存储并回显，可用于透传区服、账号等业务数据。',
     ],
   },
   {