Add appKey to PayAppDO and update PayOrderApi to use appKey

- Added `appKey` field to `PayAppDO` to store application secret key.
- Updated `PayOrderService` interface to include `appKey` parameter in `getOrder` and `createOrder` methods.
- Implemented `getOrder` method in `PayOrderServiceImpl` to fetch `PayOrderDO` using `appKey` and `merchantOrderId`.
- Added necessary validation and exception handling for `appKey` in `PayOrderServiceImpl`.

yudao-module-pay/yudao-module-pay-biz/src/main/java/cn/iocoder/yudao/module/pay/dal/dataobject/app/PayAppDO.java

@@ -59,4 +59,9 @@ public class PayAppDO extends BaseDO {
      */
     private String transferNotifyUrl;
 
-}
+    /**
+     * 应用密钥
+     */
+    private String appKey;
+
+}

yudao-module-pay/yudao-module-pay-biz/src/main/java/cn/iocoder/yudao/module/pay/service/order/PayOrderService.java

@@ -146,4 +146,22 @@ public interface PayOrderService {
      */
     int expireOrder();
 
-}
+    /**
+     * 获得支付订单
+     *
+     * @param appKey 应用密钥
+     * @param merchantOrderId 商户订单编号
+     * @return 支付订单
+     */
+    PayOrderDO getOrder(String appKey, String merchantOrderId);
+
+    /**
+     * 创建支付单
+     *
+     * @param reqDTO 创建请求
+     * @param appKey 应用密钥
+     * @return 支付单编号
+     */
+    Long createOrder(@Valid PayOrderCreateReqDTO reqDTO, String appKey);
+
+}

yudao-module-pay/yudao-module-pay-biz/src/main/java/cn/iocoder/yudao/module/pay/service/order/PayOrderServiceImpl.java

@@ -85,6 +85,15 @@ public class PayOrderServiceImpl implements PayOrderService {
         return orderMapper.selectByAppIdAndMerchantOrderId(appId, merchantOrderId);
     }
 
+    @Override
+    public PayOrderDO getOrder(String appKey, String merchantOrderId) {
+        PayAppDO app = appService.getAppByAppKey(appKey);
+        if (app == null) {
+            throw exception(PAY_APP_NOT_FOUND);
+        }
+        return orderMapper.selectByAppIdAndMerchantOrderId(app.getId(), merchantOrderId);
+    }
+
     @Override
     public List<PayOrderDO> getOrderList(Collection<Long> ids) {
         if (CollUtil.isEmpty(ids)) {