feat(app): add error/loading boundaries across all dashboard routes and new routes

- Add error.tsx and loading.tsx boundaries for admin, parent, student, teacher routes

- Add admin announcements edit, audit-logs overview, curriculum-map, invitation-codes, permissions, questions, roles routes

- Add admin elective detail and components, files, course-plans, users, scheduling boundaries

- Add messages group-compose route

- Add parent course-plans, elective, grades report-card, practice routes

- Add student course-plans, elective detail, error-book dialogs, grades report-card, learning study-path, leave, schedule boundaries

- Add teacher attendance report, classes boundaries, course-plans boundaries, elective, exams analytics/edit-rich/all/create/new, grades report-card, homework boundaries, leave, lesson-plans calendar

- Add auth loading, onboarding loading, api cron

src/app/(dashboard)/teacher/classes/students/page.tsx

@@ -1,20 +1,32 @@
+import type { Metadata } from "next"
 import type { JSX } from "react"
 import { Suspense } from "react"
 import { User } from "lucide-react"
+import { getTranslations } from "next-intl/server"
 
 import { requirePermission } from "@/shared/lib/auth-guard"
 import { Permissions } from "@/shared/types/permissions"
 import { getClassStudents, getTeacherClasses, getStudentsSubjectScores } from "@/modules/classes/data-access"
 import { StudentsFilters } from "@/modules/classes/components/students-filters"
 import { StudentsTable } from "@/modules/classes/components/students-table"
+import { ClassErrorBoundary } from "@/modules/classes/components/class-error-boundary"
 import { EmptyState } from "@/shared/components/ui/empty-state"
 import { Skeleton } from "@/shared/components/ui/skeleton"
 import { getParam, type SearchParams } from "@/shared/lib/search-params"
 
 export const dynamic = "force-dynamic"
 
+export async function generateMetadata(): Promise<Metadata> {
+  const t = await getTranslations("classes")
+  return {
+    title: `${t("metadata.students")} - Next_Edu`,
+    description: t("metadata.students"),
+  }
+}
+
 async function StudentsResults({ searchParams, defaultClassId }: { searchParams: Promise<SearchParams>, defaultClassId?: string }): Promise<JSX.Element> {
   const params = await searchParams
+  const t = await getTranslations("classes")
 
   const q = getParam(params, "q") || undefined
   const classId = getParam(params, "classId")
@@ -25,7 +37,7 @@ async function StudentsResults({ searchParams, defaultClassId }: { searchParams:
   // However, the requirement is "Default to showing the first class".
   // If classId param is missing, we use defaultClassId.
   const targetClassId = classId ? (classId !== "all" ? classId : undefined) : defaultClassId
-  
+
   const filteredStudents = await getClassStudents({
     q,
     classId: targetClassId,
@@ -47,9 +59,9 @@ async function StudentsResults({ searchParams, defaultClassId }: { searchParams:
     return (
       <EmptyState
         icon={User}
-        title={hasFilters ? "No students match your filters" : "No students found"}
-        description={hasFilters ? "Try clearing filters or adjusting keywords." : "There are no students in your classes yet."}
-        action={hasFilters ? { label: "Clear filters", href: "/teacher/classes/students" } : undefined}
+        title={hasFilters ? t("students.empty.noMatch") : t("students.empty.title")}
+        description={hasFilters ? t("students.empty.noMatchDescription") : t("students.empty.description")}
+        action={hasFilters ? { label: t("filters.reset"), href: "/teacher/classes/students" } : undefined}
         className="h-[360px] bg-card"
       />
     )
@@ -80,20 +92,22 @@ function StudentsResultsFallback() {
 export default async function StudentsPage({ searchParams }: { searchParams: Promise<SearchParams> }): Promise<JSX.Element> {
   await requirePermission(Permissions.CLASS_READ)
   const classes = await getTeacherClasses()
-  
+
   // Logic to determine default class (first one available)
   const defaultClassId = classes.length > 0 ? classes[0].id : undefined
 
   return (
     <div className="flex h-full flex-col space-y-4 p-8">
       <div className="space-y-4">
-        <Suspense fallback={<div className="h-10 w-full animate-pulse rounded-md bg-muted" />}>
-          <StudentsFilters classes={classes} defaultClassId={defaultClassId} />
-        </Suspense>
+        <ClassErrorBoundary>
+          <Suspense fallback={<div className="h-10 w-full animate-pulse rounded-md bg-muted" />}>
+            <StudentsFilters classes={classes} defaultClassId={defaultClassId} />
+          </Suspense>
 
-        <Suspense fallback={<StudentsResultsFallback />}>
-          <StudentsResults searchParams={searchParams} defaultClassId={defaultClassId} />
-        </Suspense>
+          <Suspense fallback={<StudentsResultsFallback />}>
+            <StudentsResults searchParams={searchParams} defaultClassId={defaultClassId} />
+          </Suspense>
+        </ClassErrorBoundary>
       </div>
     </div>
   )