feat(school,classes): 学校/年级/班级模块审计修复 — 权限校验 + i18n + 架构图同步

- 新增审计报告 docs/architecture/audit/school-grade-class-audit-report.md

- 修复 P0-4: teacher/classes 4 个页面补充 requirePermission 权限校验

- 修复 P0-5: 新增 school.json i18n 文件（zh-CN/en）并接入 schools-view 组件

- 同步架构图 004：补充 grade-management 死模块记录与 teacher/classes 权限修复说明

src/app/(dashboard)/admin/school/schools/page.tsx

@@ -1,26 +1,31 @@
-import type { Metadata } from "next"
+import type { Metadata } from "next"
 import type { JSX } from "react"
 
+import { getTranslations } from "next-intl/server"
 import { requirePermission } from "@/shared/lib/auth-guard"
 import { Permissions } from "@/shared/types/permissions"
 import { SchoolsClient } from "@/modules/school/components/schools-view"
 import { getSchools } from "@/modules/school/data-access"
 
-export const metadata: Metadata = {
-  title: "学校管理 - Next_Edu",
-  description: "多校区场景下的学校管理",
-}
-
 export const dynamic = "force-dynamic"
 
+export async function generateMetadata(): Promise<Metadata> {
+  const t = await getTranslations("school")
+  return {
+    title: `${t("schools.title")} - Next_Edu`,
+    description: t("schools.description"),
+  }
+}
+
 export default async function AdminSchoolsPage(): Promise<JSX.Element> {
   await requirePermission(Permissions.SCHOOL_MANAGE)
+  const t = await getTranslations("school")
   const schools = await getSchools()
   return (
     <div className="flex h-full flex-col space-y-8 p-8">
       <div className="space-y-1">
-        <h2 className="text-2xl font-bold tracking-tight">学校管理</h2>
-        <p className="text-muted-foreground">多校区场景下的学校管理。</p>
+        <h2 className="text-2xl font-bold tracking-tight">{t("schools.title")}</h2>
+        <p className="text-muted-foreground">{t("schools.description")}</p>
       </div>
       <SchoolsClient schools={schools} />
     </div>