fix(订单操作): 将客户ID转换为字符串类型

src/mixins/order/orderOperationsMixin.js

@@ -84,6 +84,7 @@ export default {
       // 先加载客户选项
       await this.loadCustomerOptions()
       
+      this.orderForm.customerId = this.orderForm.customerId.toString()
       // 如果当前订单有客户ID，确保该客户在选项列表中
       if (this.orderForm.customerId && this.orderForm.customerCode) {
         this.ensureCustomerInOptions(