- 4张表新增expected_quantity字段，DO/VO/DTO同步新增
- pickUp接口改造：支持传入数量，级联更新销售/客户/采购/入库订单及库存
- 销售订单RespVO新增灶点id和灶点名称，赋值逻辑参考采购订单
- 客户下单orderItemQuantity截断为小数点后两位(RoundingMode.DOWN)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>