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>

backend/src/routes/employee.routes.ts

@@ -3,7 +3,7 @@ import { authMiddleware, AuthRequest } from '../middleware/auth'
 import { auditLog } from '../middleware/auditLog'
 import { createEvidence } from '../services/evidence.service'
 import prisma from '../lib/prisma'
-import { sha256 } from '../lib/crypto'
+import { sha256, decrypt } from '../lib/crypto'
 import {
   createEmployeeSchema,
   updateEmployeeSchema,
@@ -116,6 +116,27 @@ router.get('/check-id-card', authMiddleware, async (req: AuthRequest, res, next)
   }
 })
 
+// 手机号查重
+router.get('/check-phone', authMiddleware, async (req: AuthRequest, res, next) => {
+  try {
+    const phone = req.query.phone as string
+    if (!phone || phone.length < 11) {
+      return res.json({ success: true, data: { exists: false } })
+    }
+    // 手机号加密存储，需遍历匹配（量小可接受）
+    const employees = await prisma.employee.findMany({
+      where: { orgId: req.user!.orgId },
+      select: { id: true, name: true, department: true, status: true, phone: true },
+    })
+    const matched = employees.find(e => {
+      try { return e.phone ? decrypt(e.phone) === phone : false } catch { return false }
+    })
+    res.json({ success: true, data: { exists: !!matched, employee: matched ? { id: matched.id, name: matched.name, department: matched.department, status: matched.status } : undefined } })
+  } catch (err) {
+    next(err)
+  }
+})
+
 router.post('/', authMiddleware, async (req: AuthRequest, res, next) => {
   try {
     const data = createEmployeeSchema.parse(req.body)