feat: Setup projet Classeo avec infrastructure Docker et architecture DDD

Configure l'environnement de développement complet avec Docker Compose,
structure DDD 4 Bounded Contexts, et pipeline CI/CD GitHub Actions.

Corrections compatibilité CI:
- Symfony 8 nécessite monolog-bundle ^4.0 (la v3.x ne supporte que jusqu'à Symfony 7)
- ESLint v9 nécessite flat config (eslint.config.js) - le format .eslintrc.cjs est obsolète

backend/src/Kernel.php

@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App;
+
+use Symfony\Bundle\FrameworkBundle\Kernel\MicroKernelTrait;
+use Symfony\Component\HttpKernel\Kernel as BaseKernel;
+
+final class Kernel extends BaseKernel
+{
+    use MicroKernelTrait;
+}

backend/src/Shared/Domain/AggregateRoot.php

@@ -0,0 +1,25 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Shared\Domain;
+
+abstract class AggregateRoot
+{
+    /** @var DomainEvent[] */
+    private array $domainEvents = [];
+
+    protected function recordEvent(DomainEvent $event): void
+    {
+        $this->domainEvents[] = $event;
+    }
+
+    /** @return DomainEvent[] */
+    public function pullDomainEvents(): array
+    {
+        $events = $this->domainEvents;
+        $this->domainEvents = [];
+
+        return $events;
+    }
+}

backend/src/Shared/Domain/Clock.php

@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Shared\Domain;
+
+use DateTimeImmutable;
+
+interface Clock
+{
+    public function now(): DateTimeImmutable;
+}

backend/src/Shared/Domain/CorrelationId.php

@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Shared\Domain;
+
+use Ramsey\Uuid\Uuid;
+
+final readonly class CorrelationId
+{
+    private function __construct(
+        private string $value,
+    ) {
+    }
+
+    public static function generate(): self
+    {
+        return new self(Uuid::uuid4()->toString());
+    }
+
+    public static function fromString(string $value): self
+    {
+        return new self($value);
+    }
+
+    public function value(): string
+    {
+        return $this->value;
+    }
+
+    public function __toString(): string
+    {
+        return $this->value;
+    }
+}

backend/src/Shared/Domain/DomainEvent.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Shared\Domain;
+
+use DateTimeImmutable;
+use Ramsey\Uuid\UuidInterface;
+
+interface DomainEvent
+{
+    public function occurredOn(): DateTimeImmutable;
+
+    public function aggregateId(): UuidInterface;
+}

backend/src/Shared/Domain/EntityId.php

@@ -0,0 +1,39 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Shared\Domain;
+
+use Ramsey\Uuid\Uuid;
+use Ramsey\Uuid\UuidInterface;
+
+/**
+ * @phpstan-consistent-constructor
+ */
+abstract readonly class EntityId
+{
+    protected function __construct(
+        public UuidInterface $value,
+    ) {
+    }
+
+    public static function generate(): static
+    {
+        return new static(Uuid::uuid4());
+    }
+
+    public static function fromString(string $value): static
+    {
+        return new static(Uuid::fromString($value));
+    }
+
+    public function equals(EntityId $other): bool
+    {
+        return $this->value->equals($other->value);
+    }
+
+    public function __toString(): string
+    {
+        return $this->value->toString();
+    }
+}

backend/src/Shared/Infrastructure/Clock/SystemClock.php

@@ -0,0 +1,16 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Shared\Infrastructure\Clock;
+
+use App\Shared\Domain\Clock;
+use DateTimeImmutable;
+
+final readonly class SystemClock implements Clock
+{
+    public function now(): DateTimeImmutable
+    {
+        return new DateTimeImmutable();
+    }
+}