feat: add absence notification and analytics features

- Implemented AbsenceNotifyView for notifying absence with session details.
- Created AnalyticsView for displaying group analytics and managing students at risk.
- Added ClassAttendanceView for marking attendance in classes.
- Defined new schemas for analytics and attendance in shared package.

apps/backend/src/modules/classes/features/public-notify/route.ts

@@ -0,0 +1,19 @@
+import type { PublicNotifyAbsence } from '@gruperly/shared';
+import { PublicNotifyAbsenceSchema } from '@gruperly/shared';
+import { Hono } from 'hono';
+import { resultJson } from '@/http/problem-details';
+import { validate } from '@/http/validate';
+import { PublicNotifyAbsenceUseCase } from './use-case';
+
+const route = new Hono();
+
+// Ruta pública (whitelistada en session-auth): el alumno avisa su ausencia con token.
+route.post('/notify-absence', validate.json(PublicNotifyAbsenceSchema), async (c) => {
+  const payload = c.req.valid('json') as PublicNotifyAbsence;
+  const useCase = new PublicNotifyAbsenceUseCase();
+  const result = await useCase.execute(payload);
+
+  return resultJson(c, result);
+});
+
+export default route;