feat(erp): 采购计划/采购审核/到货跟踪 + 供应商管理

- 采购计划：选合同自动带出明细、合同/供应商表格选择器、批量填充(可生成N行)、卷号/数量列、送审/重新送审流程
- 采购审核：通过/驳回 + 申请意见，每次审核留痕(erp_purchase_plan_audit_log)，计划详情展示审核历史/驳回理由
- 到货跟踪：上传到货Excel按牌号+规格回填明细到货量与状态，列校验/kg→t纠正，满额自动归档
- 供应商管理页(复用既有 erp_supplier 后端)
- 综合搜索(计划号/供货商/合同号)、左右分栏工作台、全局表单按钮对齐修复
- 清理无用旧 erp 页面(看板/需求/订单/收货/退货/汇总)
- DDL 与菜单脚本：docs/purchase-plan-ddl.sql(按 path 解析父目录、可重复执行)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

klp-erp/src/main/resources/mapper/erp/ErpPurchasePlanDeliveryMapper.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE mapper
+PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
+"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
+<mapper namespace="com.klp.erp.mapper.ErpPurchasePlanDeliveryMapper">
+
+    <select id="sumCoilWeightByPlan" resultType="java.math.BigDecimal">
+        SELECT COALESCE(SUM(coil_weight), 0)
+        FROM erp_purchase_plan_delivery
+        WHERE del_flag = '0' AND plan_id = #{planId}
+    </select>
+
+</mapper>