feat(absences) : fondation backend du module de gestion des absences

Module type Payfit (étapes 1+2 de la spec V1) : demande d'absence, validation
admin, soldes à jour.

- Enums : AbsenceType, AbsenceStatus, HalfDay, ContractType, FamilySituation
- Entités : AbsencePolicy, AbsenceBalance, AbsenceRequest + champs RH sur User
- Services : PublicHolidayProvider (fériés FR métropole en PHP pur, Computus),
  AbsenceDayCalculator (décompte jours ouvrés/ouvrables + demi-journées, TDD),
  AbsenceBalanceService (périodes + pending/taken/recrédit)
- API Platform : providers/processors (création, approve/reject/cancel) + RBAC
  me/admin, contrôleurs preview (dry-run), upload/download justificatif, calendrier
- Migrations : une par table + colonnes RH user (DEFAULT puis DROP DEFAULT)
- Fixtures : 5 policies par défaut, salariés démo, soldes et demandes
- Tests unitaires : PublicHolidayProvider, AbsenceDayCalculator (12 tests)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/Unit/Service/AbsenceDayCalculatorTest.php

@@ -0,0 +1,92 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Tests\Unit\Service;
+
+use App\Enum\HalfDay;
+use App\Service\AbsenceDayCalculator;
+use App\Service\PublicHolidayProvider;
+use DateTimeImmutable;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @internal
+ */
+class AbsenceDayCalculatorTest extends TestCase
+{
+    private AbsenceDayCalculator $calculator;
+
+    protected function setUp(): void
+    {
+        $this->calculator = new AbsenceDayCalculator(new PublicHolidayProvider());
+    }
+
+    public function testFullWeekIsFiveWorkingDays(): void
+    {
+        // Mon 2026-06-01 to Fri 2026-06-05, no holidays that week
+        self::assertSame(5.0, $this->calculator->countWorkingDays(
+            new DateTimeImmutable('2026-06-01'),
+            new DateTimeImmutable('2026-06-05'),
+        ));
+    }
+
+    public function testWeekendIsSkipped(): void
+    {
+        // Fri 2026-06-05 to Mon 2026-06-08 => Fri + Mon = 2
+        self::assertSame(2.0, $this->calculator->countWorkingDays(
+            new DateTimeImmutable('2026-06-05'),
+            new DateTimeImmutable('2026-06-08'),
+        ));
+    }
+
+    public function testHolidayIsSkipped(): void
+    {
+        // Thu 2026-05-07 to Fri 2026-05-08 (Victoire 1945) => Thu only = 1
+        self::assertSame(1.0, $this->calculator->countWorkingDays(
+            new DateTimeImmutable('2026-05-07'),
+            new DateTimeImmutable('2026-05-08'),
+        ));
+    }
+
+    public function testHalfDayStartSubtractsHalf(): void
+    {
+        self::assertSame(4.5, $this->calculator->countWorkingDays(
+            new DateTimeImmutable('2026-06-01'),
+            new DateTimeImmutable('2026-06-05'),
+            HalfDay::Afternoon,
+        ));
+    }
+
+    public function testBothHalfDaysSubtractOne(): void
+    {
+        self::assertSame(4.0, $this->calculator->countWorkingDays(
+            new DateTimeImmutable('2026-06-01'),
+            new DateTimeImmutable('2026-06-05'),
+            HalfDay::Afternoon,
+            HalfDay::Morning,
+        ));
+    }
+
+    public function testSingleHalfDay(): void
+    {
+        self::assertSame(0.5, $this->calculator->countWorkingDays(
+            new DateTimeImmutable('2026-06-01'),
+            new DateTimeImmutable('2026-06-01'),
+            HalfDay::Morning,
+        ));
+    }
+
+    public function testWorkingDaysVsOpenDays(): void
+    {
+        // Fri 2026-06-05 to Mon 2026-06-08, "ouvrables" includes Saturday
+        // => Fri + Sat + Mon = 3 (Sunday always skipped)
+        self::assertSame(3.0, $this->calculator->countWorkingDays(
+            new DateTimeImmutable('2026-06-05'),
+            new DateTimeImmutable('2026-06-08'),
+            null,
+            null,
+            false,
+        ));
+    }
+}