feat(versioning) : add entity versioning with numbered versions and restore

Backend:
- Migration: version column on audit_logs and machines
- AuditLog, Machine, Composant, Piece, Product: version + skipAudit properties
- AbstractAuditSubscriber: auto-increment version, skip on restore, fix decimal diff
- Enriched snapshots with slots, custom fields and version number
- AuditLogRepository: findVersionHistory, findByVersion
- EntityVersionService: list, preview, restore with skeleton/integrity checks
- EntityVersionController: REST endpoints for all 4 entity types
- 11 tests covering list, preview, restore, auth

Frontend: update submodule pointer

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

src/Repository/AuditLogRepository.php

@@ -35,6 +35,38 @@ final class AuditLogRepository extends ServiceEntityRepository
         ;
     }
 
+    /**
+     * @return list<AuditLog>
+     */
+    public function findVersionHistory(string $entityType, string $entityId): array
+    {
+        return $this->createQueryBuilder('a')
+            ->andWhere('a.entityType = :entityType')
+            ->andWhere('a.entityId = :entityId')
+            ->andWhere('a.version IS NOT NULL')
+            ->setParameter('entityType', $entityType)
+            ->setParameter('entityId', $entityId)
+            ->orderBy('a.version', 'DESC')
+            ->getQuery()
+            ->getResult()
+        ;
+    }
+
+    public function findByVersion(string $entityType, string $entityId, int $version): ?AuditLog
+    {
+        return $this->createQueryBuilder('a')
+            ->andWhere('a.entityType = :entityType')
+            ->andWhere('a.entityId = :entityId')
+            ->andWhere('a.version = :version')
+            ->setParameter('entityType', $entityType)
+            ->setParameter('entityId', $entityId)
+            ->setParameter('version', $version)
+            ->setMaxResults(1)
+            ->getQuery()
+            ->getOneOrNullResult()
+        ;
+    }
+
     /**
      * @param array{entityType?: string, action?: string} $filters
      *