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/app/(dashboard)/parent/attendance/page.tsx

@@ -1,3 +1,4 @@
+import { getTranslations } from "next-intl/server"
 import { getAuthContext } from "@/shared/lib/auth-guard"
 import { getStudentAttendanceSummary } from "@/modules/attendance/data-access-stats"
 import { StudentAttendanceView } from "@/modules/attendance/components/student-attendance-view"
@@ -5,21 +6,25 @@ import {
   ParentChildrenDataPage,
   ParentNoChildrenPage,
 } from "@/modules/parent/components/parent-children-data-page"
+import { ParentAttendanceWarning } from "@/modules/parent/components/parent-attendance-warning"
+import { ParentAttendanceRateCard } from "@/modules/parent/components/parent-attendance-rate-card"
+import { ParentAttendanceCalendar } from "@/modules/parent/components/parent-attendance-calendar"
 import { CalendarCheck } from "lucide-react"
 
 export const dynamic = "force-dynamic"
 
 export default async function ParentAttendancePage() {
+  const t = await getTranslations("attendance")
   const ctx = await getAuthContext()
 
   if (ctx.dataScope.type !== "children" || ctx.dataScope.childrenIds.length === 0) {
     return (
       <ParentNoChildrenPage
-        title="Children Attendance"
-        description="View your children's attendance records."
+        title={t("title.parent")}
+        description={t("description.parent")}
         icon={CalendarCheck}
-        emptyTitle="No children linked"
-        emptyDescription="Your account is not linked to any student accounts yet. Please contact the school administrator."
+        emptyTitle={t("parent.noChildrenTitle")}
+        emptyDescription={t("parent.noChildrenDescription")}
       />
     )
   }
@@ -37,18 +42,27 @@ export default async function ParentAttendancePage() {
 
   return (
     <ParentChildrenDataPage
-      title="Children Attendance"
-      description="View your children's attendance records."
+      title={t("title.parent")}
+      description={t("parent.compareDescription")}
       icon={CalendarCheck}
-      noRecordsTitle="No attendance records"
-      noRecordsDescription="Your children don't have any attendance records yet."
+      noRecordsTitle={t("list.empty")}
+      noRecordsDescription={t("parent.noRecordsDescription")}
       items={validSummaries}
       renderItem={(summary) => (
-        <>
+        <div className="space-y-6">
           <h3 className="text-lg font-semibold border-b pb-2">{summary.studentName}</h3>
+          <ParentAttendanceCalendar summary={summary} />
           <StudentAttendanceView summary={summary} />
-        </>
+        </div>
       )}
+      headerExtra={
+        validSummaries.length > 0 ? (
+          <div className="space-y-4">
+            <ParentAttendanceRateCard summaries={validSummaries} />
+            <ParentAttendanceWarning summaries={validSummaries} />
+          </div>
+        ) : null
+      }
     />
   )
 }