fix(logistics): 修复货运平台courierCompany字段处理逻辑

当courierCompany为"最优物流"时不再传递空字符串，而是不设置shipCompany字段

src/service/logistics.service.ts

@@ -733,10 +733,15 @@ export class LogisticsService {
       }
 
       if (data.shipmentPlatform === 'freightwaves') {
+
+        let courierCompany: string = "";
+        if (data.courierCompany != "最优物流") {
+          courierCompany = data.courierCompany;
+        }
         // 根据TMS系统对接说明文档格式化参数
         const reqBody: any = {
           // shipCompany: 'UPSYYZ7000NEW',
-          shipCompany: data.courierCompany || "",
+          shipCompany: courierCompany,
           partnerOrderNumber: order.siteId + '-' + order.externalOrderId,
           warehouseId: '25072621030107400060',
           shipper: {
@@ -836,10 +841,14 @@ export class LogisticsService {
     })
 
     const address = shipments?.address;
+    let courierCompany: string = "";
+    if (data.courierCompany != "最优物流") {
+      courierCompany = data.courierCompany;
+    }
     // 转换为RateTryRequest格式
     const r = {
       // shipCompany: 'UPSYYZ7000NEW',
-      shipCompany: data.courierCompany || "",
+      shipCompany: courierCompany,
       partnerOrderNumber: `order-${Date.now()}`, // 必填，使用时间戳生成
       warehouseId: '25072621030107400060', // 可选，使用stockPointId转换
       shipper: {