feat(sync) : add ModelTypeSyncService orchestrator and controller with tests

Implement the sync orchestrator that delegates to tagged strategies via
AutowireIterator, and the HTTP controller exposing sync-preview and sync
endpoints with transaction wrapping and role-based access control.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/Service/ModelTypeSyncService.php

@@ -0,0 +1,44 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Service;
+
+use App\DTO\SyncConfirmation;
+use App\DTO\SyncExecutionResult;
+use App\DTO\SyncPreviewResult;
+use App\Entity\ModelType;
+use App\Service\Sync\SyncStrategyInterface;
+use LogicException;
+use Symfony\Component\DependencyInjection\Attribute\AutowireIterator;
+
+class ModelTypeSyncService
+{
+    /** @param iterable<SyncStrategyInterface> $strategies */
+    public function __construct(
+        #[AutowireIterator('app.sync_strategy')]
+        private readonly iterable $strategies,
+    ) {}
+
+    public function preview(ModelType $modelType, array $newStructure): SyncPreviewResult
+    {
+        foreach ($this->strategies as $strategy) {
+            if ($strategy->supports($modelType)) {
+                return $strategy->preview($modelType, $newStructure);
+            }
+        }
+
+        throw new LogicException('No sync strategy found for category: '.$modelType->getCategory()->value);
+    }
+
+    public function execute(ModelType $modelType, SyncConfirmation $confirmation): SyncExecutionResult
+    {
+        foreach ($this->strategies as $strategy) {
+            if ($strategy->supports($modelType)) {
+                return $strategy->execute($modelType, $confirmation);
+            }
+        }
+
+        throw new LogicException('No sync strategy found for category: '.$modelType->getCategory()->value);
+    }
+}