feat(app): add lesson-plans, practice, and grade dashboard routes

- Add admin/lesson-plans, parent/lesson-plans, student/lesson-plans routes

- Add student/practice and teacher/practice routes for adaptive practice

- Add management/grade/dashboard and management/grade/practice routes

- Add teacher/lesson-plans error and loading boundaries

- Update existing admin, parent, student, teacher pages with new features

- Update globals.css and proxy middleware

src/app/(dashboard)/teacher/lesson-plans/[planId]/edit/loading.tsx

@@ -0,0 +1,11 @@
+import { Skeleton } from "@/shared/components/ui/skeleton"
+
+export default function TeacherEditLessonPlanLoading() {
+  return (
+    <div className="h-[calc(100vh-4rem)]">
+      <div className="flex h-full items-center justify-center">
+        <Skeleton className="h-[80%] w-[80%]" />
+      </div>
+    </div>
+  )
+}