feat: 20260815 系统优化 - 全部31项问题修复(P0×6+P1×14+P2×9+P3×2)

P0紧急修复(6项):
- 草稿保存完整恢复所有字段(含socialAvgWage)
- 补偿金批次从compensationBreakdown读取
- 违法解除风险确认UI
- 合同结束日期前后校验(前后端双保险)

P1高优先级(14项):
- 离职日期联动社保/公积金截止月(15号规则)
- 合规检查+工作交接改为软阻断(生成待办)
- 补偿月数(N/N+1/2N/自定义)+计算基数(近12月/合同/自定义)
- 解聘并入花名册操作栏(类型选择跳转向导)
- 合同续签开始日期自动推导(原合同结束日+1天)
- 年龄合规筛查(童工阻断/未成年工/退休警告)
- 编辑入职日期后状态联动(待入职↔在职)
- 转正移植到花名册操作栏+薪资回写
- 男职工无法选择三期

P2体验优化(9项):
- "劳动合同"调整为"用工关系"
- 费用结算新增剩余年假折算(300%日工资)
- 身份证号全域改为"证件号码"(前后端18个文件)
- 手机号查重
- 开具证明+合同续签移植到花名册操作栏
- 批量转正+批量开具证明
- 去掉用工办理模块

P3规划(2项):
- 组织架构+审批流(Department/Position/ApprovalFlow/ApprovalInstance)
- 客服工作台(Ticket/ChatSession+SUPPORT角色)

新增模型: Department/Position/ApprovalFlow/ApprovalInstance/Ticket/TicketMessage/ChatSession/ChatMessage
新增字段: Employee.departmentId/supervisorId
新增角色: SUPPORT

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

frontend/package-lock.json

@@ -16,7 +16,7 @@
         "file-saver": "^2.0.5",
         "jspdf": "^4.2.1",
         "lucide-react": "^0.428.0",
-        "mammoth": "^1.12.0",
+        "mammoth": "^1.12.1",
         "qrcode.react": "^4.0.1",
         "react": "^18.3.1",
         "react-dom": "^18.3.1",
@@ -3348,9 +3348,9 @@
       }
     },
     "node_modules/mammoth": {
-      "version": "1.12.0",
-      "resolved": "https://registry.npmmirror.com/mammoth/-/mammoth-1.12.0.tgz",
-      "integrity": "sha512-cwnK1RIcRdDMi2HRx2EXGYlxqIEh0Oo3bLhorgnsVJi2UkbX1+jKxuBNR9PC5+JaX7EkmJxFPmo6mjLpqShI2w==",
+      "version": "1.12.1",
+      "resolved": "https://registry.npmmirror.com/mammoth/-/mammoth-1.12.1.tgz",
+      "integrity": "sha512-nCH9KKjWi3jQ+i8bUKs7k1yrXtSEGpWgF8IYkzsFMcbn+5S6l4bZEBbyx2hOQErFiXPuAs9RPa6qjXVxhyx/8g==",
       "license": "BSD-2-Clause",
       "dependencies": {
         "@xmldom/xmldom": "^0.8.6",