bug #1043 [AI Bundle] Enabling translations breaks container dumping (VincentLanglet)

This PR was squashed before being merged into the main branch.

Discussion
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[AI Bundle] Enabling translations breaks container dumping

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Docs?         | no <!-- required for new features -->
| Issues        | Fix #1040
| License       | MIT

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Commits
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b86f048 [AI Bundle] Enabling translations breaks container dumping

Author: OskarStark

src/ai-bundle/src/AiBundle.php

@@ -881,7 +881,12 @@ private function processAgentConfig(string $name, array $config, ContainerBuilde
                         throw new RuntimeException('For using prompt translataion, symfony/translation package is required. Try running "composer require symfony/translation".');
                     }
 
-                    $prompt = new TranslatableMessage($promptText, domain: $config['prompt']['translation_domain']);
+                    $promptId = 'ai.agent.prompt.'.$name;
+                    $translatableDefinition = (new Definition(TranslatableMessage::class))
+                        ->setArguments([$promptText, [], $config['prompt']['translation_domain']]);
+
+                    $container->setDefinition($promptId, $translatableDefinition);
+                    $prompt = new Reference($promptId);
                 } else {
                     $prompt = $promptText;
                 }

src/ai-bundle/tests/DependencyInjection/AiBundleTest.php

@@ -73,7 +73,6 @@
 use Symfony\Component\DependencyInjection\Reference;
 use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 use Symfony\Component\HttpClient\HttpClient;
-use Symfony\Component\Translation\TranslatableMessage;
 use Symfony\Contracts\HttpClient\HttpClientInterface;
 
 class AiBundleTest extends TestCase
@@ -2957,11 +2956,18 @@ public function testSystemPromptWithArrayStructure()
             ],
         ]);
 
+        $this->assertTrue($container->hasDefinition('ai.agent.prompt.test_agent'));
+        $definition = $container->getDefinition('ai.agent.prompt.test_agent');
+        $arguments = $definition->getArguments();
+        $this->assertEquals('You are a helpful assistant.', $arguments[0]);
+        $this->assertEquals([], $arguments[1]);
+        $this->assertEquals('prompts', $arguments[2]);
+
         $this->assertTrue($container->hasDefinition('ai.agent.test_agent.system_prompt_processor'));
         $definition = $container->getDefinition('ai.agent.test_agent.system_prompt_processor');
         $arguments = $definition->getArguments();
 
-        $this->assertEquals(new TranslatableMessage('You are a helpful assistant.', domain: 'prompts'), $arguments[0]);
+        $this->assertEquals(new Reference('ai.agent.prompt.test_agent'), $arguments[0]);
         $this->assertNull($arguments[1]); // include_tools is false, so null reference
     }