feat: 社保公积金版本管理 + 员工基数调整 + 加班费计算优化 + UI组件改进

- SocialInsuranceConfig 版本化（effectiveFrom/effectiveTo/isCurrent/adjustmentDone）
- 社保配置版本管理接口（列表/新建/按月获取/当前版本）
- 员工基数调整：预览全部在职员工、上年月均工资计算建议基数、可编辑表格、确认后批量保存
- payroll.service 按批次月份匹配对应版本社保配置
- risk.service / seed.ts 同步更新
- 前端社保tab重构为版本管理+调整+试算
- 加班费计算三步流程、CSV导入、批次导入
- UI组件、Dashboard、合同、薪酬等页面优化

frontend/src/pages/portal/ContractConfirm.tsx

@@ -48,7 +48,7 @@ export default function ContractConfirm() {
       <div className="min-h-screen flex items-center justify-center bg-gray-50 px-4">
         <div className="max-w-sm w-full text-center">
           <Check className="w-16 h-16 text-safe mx-auto mb-4" />
-          <h1 className="text-lg font-semibold mb-2">合同签署确认成功</h1>
+          <h1 className="text-sm font-semibold mb-2">合同签署确认成功</h1>
           <p className="text-sm text-gray-500">已记录您的签署确认时间和 IP 地址。</p>
         </div>
       </div>
@@ -60,7 +60,7 @@ export default function ContractConfirm() {
       <div className="max-w-md mx-auto">
         <div className="flex items-center gap-2 mb-6">
           <PenTool className="w-6 h-6 text-primary" />
-          <h1 className="text-lg font-semibold">合同签署确认</h1>
+          <h1 className="text-sm font-semibold">合同签署确认</h1>
         </div>
 
         {loading ? (
@@ -74,7 +74,7 @@ export default function ContractConfirm() {
           </Card>
         ) : data ? (
           <Card>
-            <div className="space-y-4">
+            <div className="space-y-3">
               <div className="text-sm text-gray-600">
                 {data.orgName} 与 {data.employeeName} 的劳动合同
               </div>

frontend/src/pages/portal/MyContract.tsx

@@ -37,7 +37,7 @@ export default function MyContract() {
         <div className="flex items-center justify-between mb-6">
           <div className="flex items-center gap-2">
             <FileText className="w-6 h-6 text-primary" />
-            <h1 className="text-lg font-semibold">我的劳动合同</h1>
+            <h1 className="text-sm font-semibold">我的劳动合同</h1>
           </div>
           <div className="flex items-center gap-3">
             <span className="text-sm text-gray-500">{employee.name}</span>
@@ -51,7 +51,7 @@ export default function MyContract() {
           ) : !contract ? (
             <EmptyState title="暂无合同" description="HR 尚未录入您的合同信息" />
           ) : (
-            <div className="space-y-4">
+            <div className="space-y-3">
               {/* 到期提醒 */}
               {daysToExpire !== null && daysToExpire <= 30 && daysToExpire >= 0 && (
                 <div className="flex items-center gap-2 px-3 py-2 rounded-md bg-yellow-50 text-yellow-700 text-sm">

frontend/src/pages/portal/Onboarding.tsx

@@ -53,7 +53,7 @@ export default function Onboarding() {
       <div className="min-h-screen flex items-center justify-center bg-gray-50 px-4">
         <div className="max-w-sm w-full text-center">
           <Check className="w-16 h-16 text-safe mx-auto mb-4" />
-          <h1 className="text-lg font-semibold mb-2">信息提交成功</h1>
+          <h1 className="text-sm font-semibold mb-2">信息提交成功</h1>
           <p className="text-sm text-gray-500">HR 将审核您的信息，请耐心等待。</p>
         </div>
       </div>
@@ -65,7 +65,7 @@ export default function Onboarding() {
       <div className="max-w-md mx-auto">
         <div className="flex items-center gap-2 mb-6">
           <ClipboardList className="w-6 h-6 text-primary" />
-          <h1 className="text-lg font-semibold">入职信息填报</h1>
+          <h1 className="text-sm font-semibold">入职信息填报</h1>
         </div>
 
         {orgName && (
@@ -79,7 +79,7 @@ export default function Onboarding() {
         )}
 
         <Card>
-          <div className="space-y-4">
+          <div className="space-y-3">
             <div>
               <Label>姓名 *</Label>
               <Input value={form.name} onChange={(e) => setForm({ ...form, name: e.target.value })} placeholder="请输入姓名" />

frontend/src/pages/portal/Payslip.tsx

@@ -42,7 +42,7 @@ export default function Payslip() {
         <div className="flex items-center justify-between mb-6">
           <div className="flex items-center gap-2">
             <DollarSign className="w-6 h-6 text-primary" />
-            <h1 className="text-lg font-semibold">我的工资条</h1>
+            <h1 className="text-sm font-semibold">我的工资条</h1>
           </div>
           <div className="flex items-center gap-3">
             <span className="text-sm text-gray-500">{employee.name}</span>
@@ -93,7 +93,7 @@ export default function Payslip() {
               <div className="border-t pt-3">
                 <div className="flex justify-between">
                   <span className="font-medium">应发合计</span>
-                  <span className="text-xl font-bold text-primary">¥{fmt(Number(data.totalPay))}</span>
+                  <span className="text-base font-bold text-primary">¥{fmt(Number(data.totalPay))}</span>
                 </div>
               </div>
 

frontend/src/pages/portal/PortalLogin.tsx

@@ -64,7 +64,7 @@ export default function PortalLogin() {
       <div className="w-full max-w-sm">
         <div className="flex items-center justify-center gap-2 mb-8">
           <Building2 className="w-8 h-8 text-primary" />
-          <span className="text-xl font-bold">用工合规助手 — 员工端</span>
+          <span className="text-base font-bold">用工合规助手 — 员工端</span>
         </div>
 
         <div className="card">
@@ -82,7 +82,7 @@ export default function PortalLogin() {
           {error && <div className="mb-4 px-3 py-2 rounded-md bg-red-50 text-red-700 text-sm">{error}</div>}
 
           {mode === 'password' ? (
-            <div className="space-y-4">
+            <div className="space-y-3">
               <div>
                 <Label>手机号</Label>
                 <Input type="tel" placeholder="请输入手机号" value={phone} onChange={(e) => setPhone(e.target.value)} maxLength={11} />
@@ -96,7 +96,7 @@ export default function PortalLogin() {
               </Button>
             </div>
           ) : (
-            <div className="space-y-4">
+            <div className="space-y-3">
               <div>
                 <Label>手机号</Label>
                 <Input type="tel" placeholder="请输入手机号" value={phone} onChange={(e) => setPhone(e.target.value)} maxLength={11} />