Add AuditDumpRequestHandler to process audit dump requests and ensure transactional consistency

- Introduced `AuditDumpRequestHandler` to handle `AuditDumpRequestMessage` with transactional safety.
- Added custom exceptions `AuditDumpTooMuchLines` and `AuditDumpAlreadyGeneratedException` for enhanced error reporting during processing.
- Created unit tests in `AuditDumpRequestHandlerTest` to validate normal processing, exception handling, and edge cases.
- Implemented locking mechanism and state management for `StoredObject` while processing requests.

src/Bundle/ChillMainBundle/Audit/Exception/AuditDumpAlreadyGeneratedException.php

@@ -0,0 +1,14 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * Chill is a software for social workers
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Chill\MainBundle\Audit\Exception;
+
+class AuditDumpAlreadyGeneratedException extends \RuntimeException {}