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/exams/create/page.tsx

@@ -1,10 +1,13 @@
 import type { JSX } from "react"
 import { getTranslations } from "next-intl/server"
 import { ExamForm } from "@/modules/exams/components/exam-form"
+import { requirePermission } from "@/shared/lib/auth-guard"
+import { Permissions } from "@/shared/types/permissions"
 
 export const dynamic = "force-dynamic"
 
 export default async function CreateExamPage(): Promise<JSX.Element> {
+  await requirePermission(Permissions.EXAM_CREATE)
   const t = await getTranslations("examHomework")
   return (
     <div className="mx-auto w-full max-w-[1200px] space-y-6 p-6">