feat: 花名册操作联动电子签署 + 修复重复创建

## 修复
- POST /contracts 不再自动创建签署记录（由前端根据signMethod决定），避免与ContractInfo重复创建

## 新增 SignMethodChoice 通用组件
- 花名册操作成功后弹窗选择签署方式：电子签/线下手签/稍后处理
- 电子签：自动创建ESignRecord（PENDING），员工在员工端签署
- 线下手签：跳转签署页面，预填员工/场景/标题，上传扫描件登记
- 稍后处理：跳过，可后续在签署页面手动发起

## 花名册4项操作联动签署方式选择
- 重新入职：操作成功后弹窗（scene=CONTRACT，劳动合同）
- 合同续签：操作成功后弹窗（scene=CONTRACT，续签劳动合同）
- 薪酬变更：操作成功后弹窗（scene=POLICY，薪酬调整确认书）
- 调岗调动：操作成功后弹窗（scene=POLICY，调岗确认书）

## ESign页面支持URL参数
- 读取 ?action=paper-sign 自动打开线下手签登记Modal
- 预填employeeId/scene/documentTitle

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

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

frontend/src/pages/ESign.tsx

@@ -6,7 +6,8 @@
  * - 签署详情（含证据链查看）
  * - 取消签署
  */
-import { useState, useRef } from 'react'
+import { useState, useRef, useEffect } from 'react'
+import { useSearchParams } from 'react-router-dom'
 import { toast } from 'sonner'
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query'
 import { PenTool, Plus, RefreshCw, ExternalLink, FileText, AlertCircle, Shield, ChevronLeft, Clock, CheckCircle2, XCircle, Eye, Upload, FileCheck } from 'lucide-react'
@@ -47,6 +48,7 @@ export default function ESign() {
   const [showCreate, setShowCreate] = useState(false)
   const [showPaperSign, setShowPaperSign] = useState(false)
   const [detailId, setDetailId] = useState<string | null>(null)
+  const [searchParams] = useSearchParams()
   const [formData, setFormData] = useState({
     employeeId: '',
     scene: 'CONTRACT',
@@ -54,6 +56,26 @@ export default function ESign() {
     remark: '',
   })
 
+  // 从 URL 参数读取，自动打开线下手签登记
+  useEffect(() => {
+    const action = searchParams.get('action')
+    if (action === 'paper-sign') {
+      setShowPaperSign(true)
+      // 预填表单
+      const employeeId = searchParams.get('employeeId')
+      const scene = searchParams.get('scene') as string
+      const documentTitle = searchParams.get('documentTitle') as string
+      if (employeeId || scene || documentTitle) {
+        setFormData({
+          employeeId: employeeId || '',
+          scene: scene || 'CONTRACT',
+          documentTitle: documentTitle || '',
+          remark: '花名册操作跳转登记',
+        })
+      }
+    }
+  }, [searchParams])
+
   const { data: records = [], isLoading } = useQuery<any[]>({
     queryKey: ['esign-records', filterStatus, filterScene],
     queryFn: async () => {
@@ -323,10 +345,15 @@ export default function ESign() {
       {/* 线下手签登记 Modal */}
       {showPaperSign && (
         <PaperSignModal
-          onClose={() => setShowPaperSign(false)}
+          initialEmployeeId={formData.employeeId}
+          initialScene={formData.scene as any}
+          initialDocumentTitle={formData.documentTitle}
+          initialRemark={formData.remark}
+          onClose={() => { setShowPaperSign(false); setFormData({ employeeId: '', scene: 'CONTRACT', documentTitle: '', remark: '' }) }}
           onSuccess={() => {
             queryClient.invalidateQueries({ queryKey: ['esign-records'] })
             setShowPaperSign(false)
+            setFormData({ employeeId: '', scene: 'CONTRACT', documentTitle: '', remark: '' })
           }}
         />
       )}
@@ -335,17 +362,24 @@ export default function ESign() {
 }
 
 // ===== 线下手签登记 Modal =====
-function PaperSignModal({ onClose, onSuccess }: { onClose: () => void; onSuccess: () => void }) {
+function PaperSignModal({ onClose, onSuccess, initialEmployeeId, initialScene, initialDocumentTitle, initialRemark }: {
+  onClose: () => void
+  onSuccess: () => void
+  initialEmployeeId?: string
+  initialScene?: string
+  initialDocumentTitle?: string
+  initialRemark?: string
+}) {
   const fileInputRef = useRef<HTMLInputElement>(null)
   const [form, setForm] = useState({
-    employeeId: '',
-    scene: 'CONTRACT',
-    documentTitle: '',
+    employeeId: initialEmployeeId || '',
+    scene: initialScene || 'CONTRACT',
+    documentTitle: initialDocumentTitle || '',
     signedAt: new Date().toISOString().slice(0, 10),
     signedLocation: '',
     witnessName: '',
     witnessPhone: '',
-    remark: '',
+    remark: initialRemark || '',
   })
   const [scanFiles, setScanFiles] = useState<Array<{ name: string; url: string }>>([])
   const [uploading, setUploading] = useState(false)