feat: 系统优化Phase2 - 面包屑导航/侧边栏间距/制度公示阅读签收/模板变量中文化/通知类型补全

- 面包屑导航组件，集成至TopNav header
- 侧边栏菜单分组间距增大，分组间分隔线
- 制度公示员工阅读签收：PolicyReadRecord模型、portal路由、管理端阅读统计
- 修复Policies.tsx民主程序推进bug（字段名/API路径/参数）
- 用工文本模板变量名英文转中文显示
- 通知类型TYPE_LABELS补全(RISK_ALERT/SOCIAL_INS/OVERTIME_ALERT/PAYSLIP_READY)
- 通知示例数据补充
- h2标题统一为text-sm font-medium
- 新增run.md

frontend/src/pages/Compensation.tsx

@@ -155,7 +155,7 @@ function SeveranceCalculator() {
   return (
     <div className="grid md:grid-cols-2 gap-4">
       <Card>
-        <h2 className="font-medium mb-4">填写信息</h2>
+        <h2 className="text-sm font-medium mb-4">填写信息</h2>
         <div className="space-y-3">
           <EmployeeSelector employees={employees} selectedId={selectedEmpId} onSelect={handleSelectEmp} />
           <div>
@@ -192,7 +192,7 @@ function SeveranceCalculator() {
       </Card>
 
       <Card>
-        <h2 className="font-medium mb-4 flex items-center gap-2"><Calculator className="w-5 h-5" />计算结果</h2>
+        <h2 className="text-sm font-medium mb-4 flex items-center gap-2"><Calculator className="w-5 h-5" />计算结果</h2>
         {result ? (
           <div className="space-y-3">
             <div className="text-xs text-gray-500">离职原因：<span className="text-gray-900">{result.reason}</span></div>
@@ -308,7 +308,7 @@ function DoubleSalaryCalculator() {
   return (
     <div className="grid md:grid-cols-2 gap-4">
       <Card>
-        <h2 className="font-medium mb-4">填写信息</h2>
+        <h2 className="text-sm font-medium mb-4">填写信息</h2>
         <div className="space-y-3">
           <EmployeeSelector employees={employees} selectedId={selectedEmpId} onSelect={handleSelectEmp} />
           <div>
@@ -336,7 +336,7 @@ function DoubleSalaryCalculator() {
       </Card>
 
       <Card>
-        <h2 className="font-medium mb-4 flex items-center gap-2"><AlertCircle className="w-5 h-5 text-warning" />计算结果</h2>
+        <h2 className="text-sm font-medium mb-4 flex items-center gap-2"><AlertCircle className="w-5 h-5 text-warning" />计算结果</h2>
         {result ? (
           <div className="space-y-3">
             <div className="text-xs text-gray-500">入职日期：<span className="text-gray-900">{hireDate}</span></div>