feat: 电子签全场景集成+场景筛选+设置开关

- ESignRecord 模型新增 scene 字段（CONTRACT/RESIGNATION/POLICY/PAYSLIP/ONBOARDING）
- Organization 模型新增3个电子签开关：esignPolicyEnabled/esignPayslipEnabled/esignOnboardingEnabled
- 设置页面企业信息新增电子签署设置区域，3个开关各自独立，缺省关闭
- 规章制度签收：开启电子签后，员工阅读确认时自动创建POLICY场景签署记录
- 工资条确认：开启电子签后，员工确认工资条时自动创建PAYSLIP场景签署记录
- 入职文件签署：开启电子签后，HR审批通过入职流程时自动创建ONBOARDING场景签署记录
- 电子签署列表增加场景筛选下拉（全部场景/劳动合同/离职协议/规章制度/工资条/入职文件）
- 管理端和员工端列表均展示场景标签（基于scene字段，替代硬编码判断）
- 合同和离职流程的esign调用已加scene参数

frontend/src/pages/Settings.tsx

@@ -1,7 +1,7 @@
 import { useState, useEffect } from 'react'
 import { toast } from 'sonner'
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query'
-import { Building2, Users, CreditCard, Plus, Bell, Download, Upload, FileSpreadsheet, Clock, CheckCircle, AlertCircle, ClipboardList, LayoutGrid } from 'lucide-react'
+import { Building2, Users, CreditCard, Plus, Bell, Download, Upload, FileSpreadsheet, Clock, CheckCircle, AlertCircle, ClipboardList, LayoutGrid, PenTool } from 'lucide-react'
 import { settingsApi, notificationsApi } from '../lib/api-services'
 import { useAuthStore } from '../store/authStore'
 import { getPageSize, setPageSize as setGlobalPageSize } from '../lib/pageSize'
@@ -93,6 +93,9 @@ function OrgSettings({ orgData, onSave, saving }: { orgData: any; onSave: (data:
     contactPhone: '',
     payrollFrequency: 1,
     retirementReminderEnabled: false,
+    esignPolicyEnabled: false,
+    esignPayslipEnabled: false,
+    esignOnboardingEnabled: false,
   })
 
   useEffect(() => {
@@ -103,6 +106,9 @@ function OrgSettings({ orgData, onSave, saving }: { orgData: any; onSave: (data:
         contactPhone: orgData.contactPhone || '',
         payrollFrequency: orgData.payrollFrequency || 1,
         retirementReminderEnabled: orgData.retirementReminderEnabled || false,
+        esignPolicyEnabled: orgData.esignPolicyEnabled || false,
+        esignPayslipEnabled: orgData.esignPayslipEnabled || false,
+        esignOnboardingEnabled: orgData.esignOnboardingEnabled || false,
       })
     }
   }, [orgData])
@@ -139,6 +145,36 @@ function OrgSettings({ orgData, onSave, saving }: { orgData: any; onSave: (data:
       </div>
 
       <RetirementSection enabled={form.retirementReminderEnabled} onToggle={(v) => { setForm({ ...form, retirementReminderEnabled: v }); onSave({ ...form, retirementReminderEnabled: v }) }} />
+
+      {/* 电子签设置 */}
+      <div className="mt-6 pt-6 border-t">
+        <div className="flex items-center gap-2 mb-4">
+          <PenTool className="w-5 h-5 text-primary" />
+          <h3 className="font-medium">电子签署设置</h3>
+        </div>
+        <p className="text-xs text-gray-500 mb-3">开启后，对应场景将使用电子签署替代默认确认方式。关闭则保持原有确认方式（阅读确认/点击确认）。</p>
+        <div className="space-y-3">
+          {[
+            { key: 'esignPolicyEnabled', label: '规章制度电子签', desc: '开启后制度签收升级为电子签署，缺省为阅读确认' },
+            { key: 'esignPayslipEnabled', label: '工资条电子签', desc: '开启后工资条确认升级为电子签署，缺省为点击确认' },
+            { key: 'esignOnboardingEnabled', label: '入职文件电子签', desc: '开启后入职填报时签署入职相关文件，缺省不签' },
+          ].map(item => (
+            <div key={item.key} className="flex items-center justify-between p-3 rounded-lg bg-gray-50">
+              <div>
+                <div className="text-sm font-medium">{item.label}</div>
+                <div className="text-xs text-gray-500 mt-0.5">{item.desc}</div>
+              </div>
+              <button
+                type="button"
+                onClick={() => { const v = !form[item.key as keyof typeof form]; setForm({ ...form, [item.key]: v }); onSave({ ...form, [item.key]: v }) }}
+                className={`relative inline-flex h-6 w-11 items-center rounded-full transition-colors shrink-0 ml-4 ${form[item.key as keyof typeof form] ? 'bg-primary' : 'bg-gray-300'}`}
+              >
+                <span className={`inline-block h-4 w-4 transform rounded-full bg-white transition-transform ${form[item.key as keyof typeof form] ? 'translate-x-6' : 'translate-x-1'}`} />
+              </button>
+            </div>
+          ))}
+        </div>
+      </div>
     </Card>
   )
 }