refactor(attendance,elective): 审计第二轮 — 全量完成 P0/P1 改进项

P0 修复：
- 页面层 i18n 全量补齐（admin/teacher/parent/student × attendance/elective）
- types.ts 状态标签常量迁移至 constants.ts（i18n key + Badge variant）
- 修复 getTranslations 导入路径（next-intl → next-intl/server）

P1 改进：
- 解耦 parent 模块对 attendance 类型的直接依赖（本地 view-model 类型）
- 导出纯函数（computeStats/buildWarnings/buildLotteryRankCase 等）
- 统一空状态为 EmptyState 组件
- 清理死代码读 Action（attendance 5 个 + elective 3 个）
- 预留监控埋点接口（trackEvent 13 个新事件名）
- 补齐骨架屏 loading.tsx（8 个页面）
- AlertDialog 替换 window.confirm（student-selection-view）
- a11y 改进（aria-label/role/键盘导航）

修复：
- AttendanceStatus 从 constants.ts 重导出，消除 types/constants 双源混乱
- buildWarnings 的 Translator 类型改用 ReturnType<typeof useTranslations>

src/modules/attendance/components/student-attendance-view.tsx

@@ -1,3 +1,4 @@
+import { useTranslations } from "next-intl"
 import { Card, CardContent, CardHeader, CardTitle } from "@/shared/components/ui/card"
 import { Badge } from "@/shared/components/ui/badge"
 import {
@@ -13,21 +14,23 @@ import { CalendarCheck } from "lucide-react"
 
 import { AttendanceStatsCard } from "./attendance-stats-card"
 import {
-  ATTENDANCE_STATUS_COLORS,
-  ATTENDANCE_STATUS_LABELS,
-  type StudentAttendanceSummary,
-} from "../types"
+  ATTENDANCE_STATUS_BADGE_VARIANTS,
+  ATTENDANCE_STATUS_LABEL_KEYS,
+} from "../constants"
+import type { StudentAttendanceSummary } from "../types"
 
 export function StudentAttendanceView({
   summary,
 }: {
   summary: StudentAttendanceSummary | null
 }) {
+  const t = useTranslations("attendance")
+
   if (!summary) {
     return (
       <EmptyState
-        title="No data"
-        description="Student attendance summary is not available."
+        title={t("list.empty")}
+        description={t("errors.notFound")}
         icon={CalendarCheck}
         className="border-none shadow-none"
       />
@@ -39,7 +42,9 @@ export function StudentAttendanceView({
       <div className="grid grid-cols-1 gap-4 md:grid-cols-2">
         <Card>
           <CardHeader className="pb-2">
-            <CardTitle className="text-sm font-medium text-muted-foreground">Student</CardTitle>
+            <CardTitle className="text-sm font-medium text-muted-foreground">
+              {t("list.columns.student")}
+            </CardTitle>
           </CardHeader>
           <CardContent>
             <p className="text-2xl font-bold">{summary.studentName}</p>
@@ -47,7 +52,9 @@ export function StudentAttendanceView({
         </Card>
         <Card>
           <CardHeader className="pb-2">
-            <CardTitle className="text-sm font-medium text-muted-foreground">Total Records</CardTitle>
+            <CardTitle className="text-sm font-medium text-muted-foreground">
+              {t("stats.totalRecords")}
+            </CardTitle>
           </CardHeader>
           <CardContent>
             <p className="text-2xl font-bold">{summary.stats.total}</p>
@@ -59,25 +66,25 @@ export function StudentAttendanceView({
 
       {summary.recentRecords.length === 0 ? (
         <EmptyState
-          title="No attendance records"
-          description="There are no attendance records for this student yet."
+          title={t("list.empty")}
+          description={t("list.emptyDescription")}
           icon={CalendarCheck}
           className="border-none shadow-none"
         />
       ) : (
         <Card>
           <CardHeader>
-            <CardTitle>Recent Attendance</CardTitle>
+            <CardTitle>{t("stats.recentRecords")}</CardTitle>
           </CardHeader>
           <CardContent>
             <div className="rounded-md border">
               <Table>
                 <TableHeader>
                   <TableRow>
-                    <TableHead>Date</TableHead>
-                    <TableHead>Class</TableHead>
-                    <TableHead>Status</TableHead>
-                    <TableHead>Remark</TableHead>
+                    <TableHead>{t("list.columns.date")}</TableHead>
+                    <TableHead>{t("list.columns.class")}</TableHead>
+                    <TableHead>{t("list.columns.status")}</TableHead>
+                    <TableHead>{t("list.columns.remark")}</TableHead>
                   </TableRow>
                 </TableHeader>
                 <TableBody>
@@ -86,8 +93,8 @@ export function StudentAttendanceView({
                       <TableCell className="font-medium">{r.date}</TableCell>
                       <TableCell>{r.className}</TableCell>
                       <TableCell>
-                        <Badge variant={ATTENDANCE_STATUS_COLORS[r.status]} className="capitalize">
-                          {ATTENDANCE_STATUS_LABELS[r.status]}
+                        <Badge variant={ATTENDANCE_STATUS_BADGE_VARIANTS[r.status]} className="capitalize">
+                          {t(ATTENDANCE_STATUS_LABEL_KEYS[r.status])}
                         </Badge>
                       </TableCell>
                       <TableCell className="text-muted-foreground">{r.remark ?? "-"}</TableCell>