feat: 发薪日期多选+提前N天提醒+电子签设置区域修复

- Schema: 去掉 payrollFrequency，新增 payrollDays (JSON数组) + payrollReminderDays (Int)
- 设置页: 发薪日期改为1-28号多选按钮，新增提前提醒天数设置
- 设置页: 恢复电子签署设置区域（3个开关：规章制度/工资条/入职文件）
- 工作日历: 发薪日期作为 PAYROLL_DAY 事件显示
- 工作台: 提前N天提醒发薪日期，N可配置
- TaskCenter: 新增发薪提醒分类图标
- seed文件: 更新为 payrollDays 格式

frontend/src/pages/Calendar.tsx

@@ -15,6 +15,7 @@ const EVENT_TYPE_COLORS: Record<string, string> = {
   ANNIVERSARY: 'bg-green-100 text-green-700 border-green-200',
   RISK_DEADLINE: 'bg-orange-100 text-orange-700 border-orange-200',
   RETIREMENT: 'bg-purple-100 text-purple-700 border-purple-200',
+  PAYROLL_DAY: 'bg-emerald-100 text-emerald-700 border-emerald-200',
   CUSTOM: 'bg-blue-100 text-blue-700 border-blue-200',
   MEETING: 'bg-cyan-100 text-cyan-700 border-cyan-200',
   TEAM_BUILDING: 'bg-pink-100 text-pink-700 border-pink-200',
@@ -29,6 +30,7 @@ const EVENT_TYPE_LABELS: Record<string, string> = {
   ANNIVERSARY: '入职周年',
   RISK_DEADLINE: '风险截止',
   RETIREMENT: '退休',
+  PAYROLL_DAY: '发薪日',
   CUSTOM: '自定义',
   MEETING: '会议',
   TEAM_BUILDING: '团建',

frontend/src/pages/Settings.tsx

@@ -94,7 +94,8 @@ function OrgSettings({ orgData, onSave, saving }: { orgData: any; onSave: (data:
     name: '',
     contactName: '',
     contactPhone: '',
-    payrollFrequency: 1,
+    payrollDays: [] as number[],
+    payrollReminderDays: 3,
     retirementReminderEnabled: false,
     esignPolicyEnabled: false,
     esignPayslipEnabled: false,
@@ -107,7 +108,8 @@ function OrgSettings({ orgData, onSave, saving }: { orgData: any; onSave: (data:
         name: orgData.name || '',
         contactName: orgData.contactName || '',
         contactPhone: orgData.contactPhone || '',
-        payrollFrequency: orgData.payrollFrequency || 1,
+        payrollDays: Array.isArray(orgData.payrollDays) ? orgData.payrollDays : [],
+        payrollReminderDays: orgData.payrollReminderDays ?? 3,
         retirementReminderEnabled: orgData.retirementReminderEnabled || false,
         esignPolicyEnabled: orgData.esignPolicyEnabled || false,
         esignPayslipEnabled: orgData.esignPayslipEnabled || false,
@@ -133,20 +135,106 @@ function OrgSettings({ orgData, onSave, saving }: { orgData: any; onSave: (data:
           <Input value={form.contactPhone} onChange={(e) => setForm({ ...form, contactPhone: e.target.value })} placeholder="联系电话" />
         </div>
         <div>
-          <Label>每月发薪次数</Label>
-          <Select value={String(form.payrollFrequency)} onChange={(e) => setForm({ ...form, payrollFrequency: Number(e.target.value) })}>
-            <option value="1">1次（一月一批）</option>
-            <option value="2">2次（半月一批）</option>
-            <option value="3">3次（旬批）</option>
-            <option value="4">4次（周批）</option>
-          </Select>
-          <p className="text-xs text-gray-500 mt-1">设置每月发薪批次数，系统将按此数量管理发薪批次</p>
+          <Label>发薪日期</Label>
+          <p className="text-xs text-gray-500 mt-1 mb-2">设置每月发薪日期（可多选），系统将在工作日历中显示，并提前提醒</p>
+          <div className="flex flex-wrap gap-1.5">
+            {Array.from({ length: 28 }, (_, i) => i + 1).map(day => (
+              <button
+                key={day}
+                type="button"
+                onClick={() => {
+                  const days = form.payrollDays.includes(day)
+                    ? form.payrollDays.filter(d => d !== day)
+                    : [...form.payrollDays, day].sort((a, b) => a - b)
+                  setForm({ ...form, payrollDays: days })
+                }}
+                className={`w-9 h-9 rounded-md text-xs font-medium border transition-colors ${
+                  form.payrollDays.includes(day)
+                    ? 'bg-primary text-white border-primary'
+                    : 'bg-white text-gray-600 border-gray-200 hover:bg-gray-50'
+                }`}
+              >
+                {day}
+              </button>
+            ))}
+          </div>
+          {form.payrollDays.length > 0 && (
+            <p className="text-xs text-gray-500 mt-2">已选：每月 {form.payrollDays.map(d => `${d}号`).join('、')} 发薪</p>
+          )}
+        </div>
+        <div>
+          <Label>发薪提前提醒天数</Label>
+          <div className="flex items-center gap-3">
+            <Input type="number" min={0} max={30} value={form.payrollReminderDays} onChange={(e) => setForm({ ...form, payrollReminderDays: Number(e.target.value) })} className="!w-24" />
+            <span className="text-xs text-gray-500">天前在工作台提醒发薪</span>
+          </div>
         </div>
         <Button onClick={() => onSave(form)} disabled={saving}>
           {saving ? '保存中...' : '保存'}
         </Button>
       </div>
 
+      {/* 电子签署设置 */}
+      <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>
+        <div className="space-y-4">
+          <div className="flex items-center justify-between">
+            <div>
+              <div className="text-sm font-medium">规章制度电子签</div>
+              <p className="text-xs text-gray-500 mt-0.5">开启后，员工阅读规章制度时需电子签署；关闭时保持阅读确认</p>
+            </div>
+            <button
+              type="button"
+              onClick={() => {
+                const next = !form.esignPolicyEnabled
+                setForm({ ...form, esignPolicyEnabled: next })
+                onSave({ esignPolicyEnabled: next })
+              }}
+              className={`relative inline-flex h-6 w-11 items-center rounded-full transition-colors ${form.esignPolicyEnabled ? 'bg-primary' : 'bg-gray-200'}`}
+            >
+              <span className={`inline-block h-4 w-4 transform rounded-full bg-white transition-transform ${form.esignPolicyEnabled ? 'translate-x-6' : 'translate-x-1'}`} />
+            </button>
+          </div>
+          <div className="flex items-center justify-between">
+            <div>
+              <div className="text-sm font-medium">工资条电子签</div>
+              <p className="text-xs text-gray-500 mt-0.5">开启后，员工确认工资条时需电子签署；关闭时保持点击确认</p>
+            </div>
+            <button
+              type="button"
+              onClick={() => {
+                const next = !form.esignPayslipEnabled
+                setForm({ ...form, esignPayslipEnabled: next })
+                onSave({ esignPayslipEnabled: next })
+              }}
+              className={`relative inline-flex h-6 w-11 items-center rounded-full transition-colors ${form.esignPayslipEnabled ? 'bg-primary' : 'bg-gray-200'}`}
+            >
+              <span className={`inline-block h-4 w-4 transform rounded-full bg-white transition-transform ${form.esignPayslipEnabled ? 'translate-x-6' : 'translate-x-1'}`} />
+            </button>
+          </div>
+          <div className="flex items-center justify-between">
+            <div>
+              <div className="text-sm font-medium">入职文件电子签</div>
+              <p className="text-xs text-gray-500 mt-0.5">开启后，HR审批通过入职流程时自动创建入职文件签署；关闭时不签</p>
+            </div>
+            <button
+              type="button"
+              onClick={() => {
+                const next = !form.esignOnboardingEnabled
+                setForm({ ...form, esignOnboardingEnabled: next })
+                onSave({ esignOnboardingEnabled: next })
+              }}
+              className={`relative inline-flex h-6 w-11 items-center rounded-full transition-colors ${form.esignOnboardingEnabled ? 'bg-primary' : 'bg-gray-200'}`}
+            >
+              <span className={`inline-block h-4 w-4 transform rounded-full bg-white transition-transform ${form.esignOnboardingEnabled ? 'translate-x-6' : 'translate-x-1'}`} />
+            </button>
+          </div>
+        </div>
+      </div>
+
       {/* 显示设置 */}
       <div className="mt-6 pt-6 border-t">
         <div className="flex items-center gap-2 mb-4">

frontend/src/pages/dashboard/TaskCenter.tsx

@@ -4,7 +4,7 @@
  */
 import { useQuery } from '@tanstack/react-query'
 import { Link } from 'react-router-dom'
-import { AlertCircle, Layers, FileText, Heart, ArrowRight, ListTodo } from 'lucide-react'
+import { AlertCircle, Layers, FileText, Heart, ArrowRight, ListTodo, Wallet } from 'lucide-react'
 import { dashboardApi } from '../../lib/api-services'
 import { InlineAlert } from '../../components/ui/InlineAlert'
 
@@ -27,6 +27,7 @@ interface ActionGroup {
 const categoryIcons: Record<string, typeof AlertCircle> = {
   '待办事项': AlertCircle,
   '发薪批次': Layers,
+  '发薪提醒': Wallet,
   '合同到期': FileText,
   '特殊状态': Heart,
 }

frontend/src/pages/platform/PlatformOrgs.tsx

@@ -12,7 +12,7 @@ import Button from '../../components/ui/Button'
 interface Org {
   id: string; name: string; plan: string; maxEmployees: number
   city: string | null; contactName: string | null; contactPhone: string | null
-  payrollFrequency: number; retirementReminderEnabled: boolean
+  payrollDays: number[]; retirementReminderEnabled: boolean
   createdAt: string; updatedAt: string
   employeeCount: number; userCount: number; contractCount: number; payslipCount: number
 }