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/analytics/features/update-attendee-status/use-case.ts

@@ -0,0 +1,53 @@
+import type { PrismaClient } from '@generated/prisma/client';
+import type {
+  ProblemDetails,
+  Result,
+  UpdateStudentStatus,
+  UpdateStudentStatusResult,
+} from '@gruperly/shared';
+import { err, ok } from '@gruperly/shared';
+import { noGroupAccessProblem, notFoundResourceProblem } from '@/http/problem-builders';
+import prisma from '@/lib/prisma';
+
+type UpdateAttendeeStatusDeps = {
+  db?: Pick<PrismaClient, 'attendee'>;
+};
+
+export class UpdateAttendeeStatus {
+  constructor(private readonly deps: UpdateAttendeeStatusDeps = {}) {}
+
+  async execute(
+    studentId: string,
+    userId: string,
+    payload: UpdateStudentStatus,
+  ): Promise<Result<UpdateStudentStatusResult, ProblemDetails>> {
+    const db = this.deps.db ?? prisma;
+
+    const attendee = await db.attendee.findUnique({
+      where: { id: studentId },
+      include: { group: { include: { members: { where: { userId } } } } },
+    });
+
+    if (!attendee) {
+      return err(notFoundResourceProblem('Attendee', studentId));
+    }
+
+    const isOwner = attendee.group.createdById === userId;
+    const isMember = attendee.group.members.length > 0;
+    if (!isOwner && !isMember) {
+      return err(noGroupAccessProblem());
+    }
+
+    if (attendee.status === payload.status) {
+      return ok({ attendeeId: studentId, status: payload.status });
+    }
+
+    const updated = await db.attendee.update({
+      where: { id: studentId },
+      data: { status: payload.status },
+      select: { id: true, status: true },
+    });
+
+    return ok({ attendeeId: updated.id, status: updated.status });
+  }
+}