fix: resolve messenger worker OOM by clearing EntityManager and disabling debug

Clear Doctrine identity map after each film import to prevent memory
accumulation. Run messenger with --no-debug and higher PHP memory_limit
to avoid profiling overhead in dev.

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

src/MessageHandler/ProcessImportMessageHandler.php

@@ -5,7 +5,6 @@ declare(strict_types=1);
 namespace App\MessageHandler;
 
 use App\Entity\Import;
-use App\Entity\Notification;
 use App\Gateway\LtbxdGateway;
 use App\Message\ImportFilmsBatchMessage;
 use App\Message\ProcessImportMessage;
@@ -72,12 +71,6 @@ readonly class ProcessImportMessageHandler
 
             $import->setStatus(Import::STATUS_FAILED);
             $this->em->flush();
-
-            $notification = new Notification();
-            $notification->setUser($import->getUser());
-            $notification->setMessage('L\'import a échoué.');
-            $this->em->persist($notification);
-            $this->em->flush();
         }
     }
 }