feat(mcp) : add CRUD tools for Sites, Constructeurs, Products

- 5 tools each: list, get, create, update, delete
- McpToolHelper extracted to AbstractApiTestCase for reuse
- DashboardStatsToolTest simplified to use base helpers
- 22 MCP tests pass

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/Mcp/Tool/Product/DeleteProductTool.php

@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Mcp\Tool\Product;
+
+use App\Mcp\Tool\McpToolHelper;
+use App\Repository\ProductRepository;
+use Doctrine\ORM\EntityManagerInterface;
+use Mcp\Capability\Attribute\McpTool;
+use Symfony\Bundle\SecurityBundle\Security;
+
+#[McpTool(
+    name: 'delete_product',
+    description: 'Delete a product by ID. Requires ROLE_GESTIONNAIRE.',
+)]
+class DeleteProductTool
+{
+    use McpToolHelper;
+
+    public function __construct(
+        private readonly ProductRepository $products,
+        private readonly EntityManagerInterface $em,
+        private readonly Security $security,
+    ) {}
+
+    public function __invoke(string $productId): array
+    {
+        $this->requireRole($this->security, 'ROLE_GESTIONNAIRE');
+
+        $product = $this->products->find($productId);
+
+        if (!$product) {
+            $this->mcpError('not_found', "Product not found: {$productId}");
+        }
+
+        $this->em->remove($product);
+        $this->em->flush();
+
+        return $this->jsonResponse(['deleted' => true, 'id' => $productId]);
+    }
+}