Feature: [docgen] generate documents in an async queue

The documents are now generated in a queue, using symfony messenger. This queue should be configured:

```yaml
# app/config/messenger.yaml
framework:
    messenger:
        # reset services after consuming messages
        # reset_on_message: true

        failure_transport: failed

        transports:
            # https://symfony.com/doc/current/messenger.html#transport-configuration
            async: '%env(MESSENGER_TRANSPORT_DSN)%'
            priority:
                dsn: '%env(MESSENGER_TRANSPORT_DSN)%'
            failed: 'doctrine://default?queue_name=failed'

        routing:
            # ... other messages
            'Chill\DocGeneratorBundle\Service\Messenger\RequestGenerationMessage': priority
```

`StoredObject`s now have additionnal properties:

* status (pending, failure, ready (by default) ), which explain if the document is generated;
* a generationTrialCounter, which is incremented on each generation trial, which prevent each generation more than 5 times;

The generator computation is moved from the `DocGenTemplateController` to a `Generator` (implementing `GeneratorInterface`. 

There are new methods to `Context` which allow to normalize/denormalize context data to/from a messenger's `Message`.

src/Bundle/ChillPersonBundle/Service/DocGenerator/PersonContextWithThirdParty.php

@@ -17,6 +17,7 @@ use Chill\DocGeneratorBundle\Entity\DocGeneratorTemplate;
 use Chill\DocStoreBundle\Entity\StoredObject;
 use Chill\ThirdPartyBundle\Entity\ThirdParty;
 use Chill\ThirdPartyBundle\Form\Type\PickThirdpartyDynamicType;
+use Chill\ThirdPartyBundle\Repository\ThirdPartyRepository;
 use Symfony\Component\Form\Extension\Core\Type\TextType;
 use Symfony\Component\Form\FormBuilderInterface;
 use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
@@ -30,12 +31,16 @@ class PersonContextWithThirdParty implements DocGeneratorContextWithAdminFormInt
 
     private PersonContextInterface $personContext;
 
+    private ThirdPartyRepository $thirdPartyRepository;
+
     public function __construct(
         PersonContextInterface $personContext,
-        NormalizerInterface $normalizer
+        NormalizerInterface $normalizer,
+        ThirdPartyRepository $thirdPartyRepository
     ) {
         $this->personContext = $personContext;
         $this->normalizer = $normalizer;
+        $this->thirdPartyRepository = $thirdPartyRepository;
     }
 
     public function adminFormReverseTransform(array $data): array
@@ -123,6 +128,26 @@ class PersonContextWithThirdParty implements DocGeneratorContextWithAdminFormInt
         return true;
     }
 
+    public function contextGenerationDataNormalize(DocGeneratorTemplate $template, $entity, array $data): array
+    {
+        return array_merge(
+            [
+                'thirdParty' => null === $data['thirdParty'] ? null : $data['thirdParty']->getId(),
+            ],
+            $this->personContext->contextGenerationDataNormalize($template, $entity, $data),
+        );
+    }
+
+    public function contextGenerationDataDenormalize(DocGeneratorTemplate $template, $entity, array $data): array
+    {
+        return array_merge(
+            [
+                'thirdParty' => null === $data['thirdParty'] ? null : $this->thirdPartyRepository->find($data['thirdParty']),
+            ],
+            $this->personContext->contextGenerationDataDenormalize($template, $entity, $data),
+        );
+    }
+
     public function storeGenerated(DocGeneratorTemplate $template, StoredObject $storedObject, object $entity, array $contextGenerationData): void
     {
         $this->personContext->storeGenerated($template, $storedObject, $entity, $contextGenerationData);