fix(order): 修复优惠券使用请求中的景区ID设置问题

- 将优惠券使用请求中的景区ID从缓存结果字符串改为订单实际景区ID
- 添加空值检查以避免潜在的空指针异常
- 确保景区ID正确传递为字符串格式

src/main/java/com/ycwl/basic/service/pc/impl/OrderServiceImpl.java

@@ -998,7 +998,7 @@ public class OrderServiceImpl implements OrderService {
             couponUseRequest.setOrderId(order.getId().toString());
             couponUseRequest.setOriginalAmount(cachedResult.getOriginalAmount());
             couponUseRequest.setDiscountAmount(cachedResult.getUsedCoupon().getActualDiscountAmount());
-            couponUseRequest.setScenicId(cachedResult.toString());
+            couponUseRequest.setScenicId(order.getScenicId() != null ? order.getScenicId().toString() : null);
             iCouponService.useCoupon(couponUseRequest);
         }
         if (cachedResult.getUsedVoucher() != null) {