feat : notification de fin de contrat (veille ouvrée du dernier jour) (#35)

## Objectif
Prévenir automatiquement les administrateurs, sur le **dernier jour ouvré précédant la fin d'un contrat**, qu'un salarié arrive au terme de son emploi.

## Fonctionnement
- Commande quotidienne `app:contract:end-notifications` (à brancher sur le crontab prod, ~6h ; option `--date=YYYY-MM-DD` pour test/rattrapage).
- Cible **la dernière période de contrat** d'un employé (un changement de contrat enchaîné, ex. CDD→CDI, ne notifie pas).
- Notifie sur le **dernier jour ouvré strictement avant** `endDate` (inclusif). Week-ends **et fériés** sautés → une fin de contrat le lundi est signalée dès le vendredi. Le Lundi de Pentecôte reste un jour ouvré (cohérent avec le reste de l'app).
- Une notification par admin : message « Fin de {nature} de {Nom} le {date} », catégorie `Contrat`, lien `/employees/{id}`, sans acteur.
- **Idempotent** : déduplication par `(recipient, category, target, message)`.
- Front : la cloche (déjà admin-only) affiche proprement les notifs sans acteur.
- **Aucune migration** (réutilise la table `notifications`).

## Architecture
Logique pure isolée et testée : `WorkingDayCalculator` (week-end + férié) + `ContractEndNotificationPlanner` (fenêtre + message). Persistance dans `ContractEndNotificationService`, exposée par `ContractEndNotificationCommand`. Méthodes repo `findLatestPeriodsForAllEmployees` + `existsForRecipientCategoryTargetMessage`.

## Tests & vérification
- 11 tests unitaires ajoutés ; suite complète verte (264 tests, 564 assertions).
- Vérif e2e manuelle : run du vendredi → 6 notifs/1 contrat finissant le lundi (saut de week-end OK), relance idempotente (0), contenu BDD correct.

## Documentation
`doc/contract-end-notifications.md`, `doc/functional-rules.md` (§15), doc in-app (`documentation-content.ts`), `CLAUDE.md`.

## ⚠️ Tâche infra
Ajouter la ligne crontab prod : `0 6 * * * … bin/console app:contract:end-notifications`

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Reviewed-on: #35
Co-authored-by: tristan <tristan@yuno.malio.fr>
Co-committed-by: tristan <tristan@yuno.malio.fr>

src/Service/Notification/ContractEndNotice.php

@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Service\Notification;
+
+final readonly class ContractEndNotice
+{
+    public function __construct(
+        public ?int $employeeId,
+        public string $message,
+    ) {}
+}

src/Service/Notification/ContractEndNotificationPlanner.php

@@ -0,0 +1,70 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Service\Notification;
+
+use App\Entity\EmployeeContractPeriod;
+use App\Enum\ContractNature;
+use DateTimeImmutable;
+
+final readonly class ContractEndNotificationPlanner
+{
+    public function __construct(
+        private WorkingDayCalculator $calculator,
+    ) {}
+
+    /**
+     * @param EmployeeContractPeriod[] $latestPeriods
+     *
+     * @return ContractEndNotice[]
+     */
+    public function plan(array $latestPeriods, DateTimeImmutable $today): array
+    {
+        $today = $today->setTime(0, 0, 0);
+        if (!$this->calculator->isWorkingDay($today)) {
+            return [];
+        }
+
+        $upperBound = $this->calculator->nextWorkingDay($today);
+
+        $notices = [];
+        foreach ($latestPeriods as $period) {
+            $endDate = $period->getEndDate();
+            if (null === $endDate) {
+                continue;
+            }
+
+            $endDate = $endDate->setTime(0, 0, 0);
+            if ($endDate <= $today || $endDate > $upperBound) {
+                continue;
+            }
+
+            $employee = $period->getEmployee();
+            if (null === $employee) {
+                continue;
+            }
+
+            $message = sprintf(
+                'Fin de %s de %s %s le %s',
+                $this->natureLabel($period->getContractNatureEnum()),
+                $employee->getFirstName(),
+                $employee->getLastName(),
+                $endDate->format('d/m/Y'),
+            );
+
+            $notices[] = new ContractEndNotice($employee->getId(), $message);
+        }
+
+        return $notices;
+    }
+
+    private function natureLabel(ContractNature $nature): string
+    {
+        return match ($nature) {
+            ContractNature::CDI     => 'CDI',
+            ContractNature::CDD     => 'CDD',
+            ContractNature::INTERIM => 'Intérim',
+        };
+    }
+}

src/Service/Notification/ContractEndNotificationResult.php

@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Service\Notification;
+
+final readonly class ContractEndNotificationResult
+{
+    public function __construct(
+        public int $notificationsCreated,
+        public int $contractsMatched,
+    ) {}
+}

src/Service/Notification/ContractEndNotificationService.php

@@ -0,0 +1,73 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Service\Notification;
+
+use App\Entity\Notification;
+use App\Repository\EmployeeContractPeriodRepository;
+use App\Repository\NotificationRepository;
+use App\Repository\UserRepository;
+use DateTimeImmutable;
+use Doctrine\ORM\EntityManagerInterface;
+
+use function count;
+
+final readonly class ContractEndNotificationService
+{
+    private const CATEGORY = 'Contrat';
+
+    public function __construct(
+        private EmployeeContractPeriodRepository $periodRepository,
+        private NotificationRepository $notificationRepository,
+        private UserRepository $userRepository,
+        private ContractEndNotificationPlanner $planner,
+        private EntityManagerInterface $entityManager,
+    ) {}
+
+    public function run(DateTimeImmutable $today): ContractEndNotificationResult
+    {
+        $latestPeriods = $this->periodRepository->findLatestPeriodsForAllEmployees();
+        $notices       = $this->planner->plan($latestPeriods, $today);
+
+        if ([] === $notices) {
+            return new ContractEndNotificationResult(0, 0);
+        }
+
+        $admins  = $this->userRepository->findAllAdmins();
+        $created = 0;
+
+        foreach ($notices as $notice) {
+            if (null === $notice->employeeId) {
+                continue;
+            }
+
+            $target = '/employees/'.$notice->employeeId;
+
+            foreach ($admins as $admin) {
+                if ($this->notificationRepository->existsForRecipientCategoryTargetMessage(
+                    $admin,
+                    self::CATEGORY,
+                    $target,
+                    $notice->message,
+                )) {
+                    continue;
+                }
+
+                $notification = new Notification();
+                $notification->setRecipient($admin)
+                    ->setMessage($notice->message)
+                    ->setCategory(self::CATEGORY)
+                    ->setTarget($target)
+                ;
+
+                $this->entityManager->persist($notification);
+                ++$created;
+            }
+        }
+
+        $this->entityManager->flush();
+
+        return new ContractEndNotificationResult($created, count($notices));
+    }
+}

src/Service/Notification/WorkingDayCalculator.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Service\Notification;
+
+use App\Service\PublicHolidayServiceInterface;
+use DateTimeImmutable;
+use Throwable;
+
+final readonly class WorkingDayCalculator
+{
+    public function __construct(
+        private PublicHolidayServiceInterface $holidays,
+    ) {}
+
+    public function isWorkingDay(DateTimeImmutable $date): bool
+    {
+        $dayOfWeek = (int) $date->format('N'); // 1 (lundi) .. 7 (dimanche)
+        if ($dayOfWeek >= 6) {
+            return false;
+        }
+
+        return !$this->isPublicHoliday($date);
+    }
+
+    public function nextWorkingDay(DateTimeImmutable $date): DateTimeImmutable
+    {
+        $candidate = $date->modify('+1 day')->setTime(0, 0, 0);
+        while (!$this->isWorkingDay($candidate)) {
+            $candidate = $candidate->modify('+1 day');
+        }
+
+        return $candidate;
+    }
+
+    private function isPublicHoliday(DateTimeImmutable $date): bool
+    {
+        try {
+            $holidays = $this->holidays->getHolidaysDayByYears('metropole', $date->format('Y'));
+        } catch (Throwable) {
+            return false;
+        }
+
+        return isset($holidays[$date->format('Y-m-d')]);
+    }
+}