feat(receipt): 添加客户编号字段

- 在 Receipt 结构体中新增 CustomNumber 字段
- 用于存储客户的唯一标识信息
- 支持后续按客户编号查询和统计功能

erp/expense.go

@@ -130,3 +130,13 @@ func (r *expense) Ik3cloud(ctx context.Context, expenseId int64) (err error) {
 	reply := 0
 	return xClient.Call(ctx, "Ik3cloud", expenseId, &reply)
 }
+
+// Cancel @TITLE 作废
+func (r *expense) Cancel(ctx context.Context, expenseId int64) (err error) {
+	xClient, err := client.GetClient(r)
+	if err != nil {
+		return
+	}
+	reply := 0
+	return xClient.Call(ctx, "Cancel", expenseId, &reply)
+}