feat: Permettre la création et modification de l'emploi du temps des classes

L'administration a besoin de construire et maintenir les emplois du temps
hebdomadaires pour chaque classe, en s'assurant que les enseignants ne sont
pas en conflit (même créneau, classes différentes) et que les affectations
enseignant-matière-classe sont respectées.

Cette implémentation couvre le CRUD complet des créneaux (ScheduleSlot),
la détection de conflits (classe, enseignant, salle) avec possibilité de
forcer, la validation des affectations côté serveur (AC2), l'intégration
calendrier pour les jours bloqués, une vue mobile-first avec onglets jour
par jour, et le drag-and-drop pour réorganiser les créneaux sur desktop.

backend/tests/Unit/Scolarite/Application/Command/DeleteScheduleSlot/DeleteScheduleSlotHandlerTest.php

@@ -0,0 +1,105 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Tests\Unit\Scolarite\Application\Command\DeleteScheduleSlot;
+
+use App\Administration\Domain\Model\SchoolClass\ClassId;
+use App\Administration\Domain\Model\Subject\SubjectId;
+use App\Administration\Domain\Model\User\UserId;
+use App\Scolarite\Application\Command\DeleteScheduleSlot\DeleteScheduleSlotCommand;
+use App\Scolarite\Application\Command\DeleteScheduleSlot\DeleteScheduleSlotHandler;
+use App\Scolarite\Domain\Event\CoursSupprime;
+use App\Scolarite\Domain\Exception\ScheduleSlotNotFoundException;
+use App\Scolarite\Domain\Model\Schedule\DayOfWeek;
+use App\Scolarite\Domain\Model\Schedule\ScheduleSlot;
+use App\Scolarite\Domain\Model\Schedule\TimeSlot;
+use App\Scolarite\Infrastructure\Persistence\InMemory\InMemoryScheduleSlotRepository;
+use App\Shared\Domain\Clock;
+use App\Shared\Domain\Tenant\TenantId;
+use DateTimeImmutable;
+use PHPUnit\Framework\Attributes\Test;
+use PHPUnit\Framework\TestCase;
+
+final class DeleteScheduleSlotHandlerTest extends TestCase
+{
+    private const string TENANT_ID = '550e8400-e29b-41d4-a716-446655440001';
+    private const string CLASS_ID = '550e8400-e29b-41d4-a716-446655440020';
+    private const string SUBJECT_ID = '550e8400-e29b-41d4-a716-446655440030';
+    private const string TEACHER_ID = '550e8400-e29b-41d4-a716-446655440010';
+
+    private InMemoryScheduleSlotRepository $repository;
+    private DeleteScheduleSlotHandler $handler;
+
+    protected function setUp(): void
+    {
+        $this->repository = new InMemoryScheduleSlotRepository();
+        $clock = new class implements Clock {
+            public function now(): DateTimeImmutable
+            {
+                return new DateTimeImmutable('2026-03-02 15:00:00');
+            }
+        };
+
+        $this->handler = new DeleteScheduleSlotHandler($this->repository, $clock);
+    }
+
+    #[Test]
+    public function deletesSlotFromRepository(): void
+    {
+        $slot = $this->createAndSaveSlot();
+        $tenantId = TenantId::fromString(self::TENANT_ID);
+
+        ($this->handler)(new DeleteScheduleSlotCommand(
+            tenantId: self::TENANT_ID,
+            slotId: (string) $slot->id,
+        ));
+
+        self::assertNull($this->repository->findById($slot->id, $tenantId));
+    }
+
+    #[Test]
+    public function returnsSlotWithCoursSupprime(): void
+    {
+        $slot = $this->createAndSaveSlot();
+        $slot->pullDomainEvents(); // Clear creation event
+
+        $deletedSlot = ($this->handler)(new DeleteScheduleSlotCommand(
+            tenantId: self::TENANT_ID,
+            slotId: (string) $slot->id,
+        ));
+
+        $events = $deletedSlot->pullDomainEvents();
+        self::assertCount(1, $events);
+        self::assertInstanceOf(CoursSupprime::class, $events[0]);
+    }
+
+    #[Test]
+    public function throwsWhenSlotNotFound(): void
+    {
+        $this->expectException(ScheduleSlotNotFoundException::class);
+
+        ($this->handler)(new DeleteScheduleSlotCommand(
+            tenantId: self::TENANT_ID,
+            slotId: '550e8400-e29b-41d4-a716-446655440099',
+        ));
+    }
+
+    private function createAndSaveSlot(): ScheduleSlot
+    {
+        $slot = ScheduleSlot::creer(
+            tenantId: TenantId::fromString(self::TENANT_ID),
+            classId: ClassId::fromString(self::CLASS_ID),
+            subjectId: SubjectId::fromString(self::SUBJECT_ID),
+            teacherId: UserId::fromString(self::TEACHER_ID),
+            dayOfWeek: DayOfWeek::MONDAY,
+            timeSlot: new TimeSlot('08:00', '09:00'),
+            room: null,
+            isRecurring: true,
+            now: new DateTimeImmutable('2026-03-01 10:00:00'),
+        );
+        $this->repository->save($slot);
+
+        return $slot;
+    }
+}