Step 05 — Hardening

- CorrelationId VO pour le tracing inter-BC
- IdempotencyStore (interface + InMemory) pour garde d'idempotence
- correlationId ajouté aux contrats Published Language (retro-compatible par défaut)
- Consumers Invoicing et LegacyFulfillment idempotents avec logging
- MessengerSalesEventPublisher propage les correlationIds
- Tests unitaires idempotence + tests d'intégration consommateurs idempotents

tests/Unit/Shared/IdempotencyTest.php

@@ -0,0 +1,36 @@
+<?php
+
+declare(strict_types=1);
+
+namespace MiniShop\Tests\Unit\Shared;
+
+use MiniShop\Shared\Technical\InMemoryIdempotencyStore;
+use PHPUnit\Framework\TestCase;
+
+final class IdempotencyTest extends TestCase
+{
+    public function test_first_call_is_not_duplicate(): void
+    {
+        $store = new InMemoryIdempotencyStore();
+
+        self::assertFalse($store->isDuplicate('key-1'));
+    }
+
+    public function test_second_call_is_duplicate(): void
+    {
+        $store = new InMemoryIdempotencyStore();
+
+        $store->isDuplicate('key-1');
+
+        self::assertTrue($store->isDuplicate('key-1'));
+    }
+
+    public function test_different_keys_are_independent(): void
+    {
+        $store = new InMemoryIdempotencyStore();
+
+        $store->isDuplicate('key-1');
+
+        self::assertFalse($store->isDuplicate('key-2'));
+    }
+}