[AiBundle] Add configuration support for platform tools

Platforms can now be configured as tools in agent definitions:

ai:
  agent:
    my_agent:
      tools:
        - platform: 'elevenlabs'
          model: 'scribe_v1'
          name: 'transcribe_audio'
          description: 'Transcribes audio files to text'
          options: []

This allows agents to use specialized platforms as tools, enabling
scenarios like an OpenAI agent using ElevenLabs for speech-to-text.

Author: OskarStark

src/ai-bundle/config/options.php

@@ -391,6 +391,12 @@
                                         ->children()
                                             ->stringNode('service')->cannotBeEmpty()->end()
                                             ->stringNode('agent')->cannotBeEmpty()->end()
+                                            ->stringNode('platform')->cannotBeEmpty()->end()
+                                            ->stringNode('model')->cannotBeEmpty()->end()
+                                            ->arrayNode('options')
+                                                ->info('Options to pass to the platform')
+                                                ->scalarPrototype()->end()
+                                            ->end()
                                             ->stringNode('name')->end()
                                             ->stringNode('description')->end()
                                             ->stringNode('method')->end()
@@ -402,8 +408,27 @@
                                             })
                                         ->end()
                                         ->validate()
-                                            ->ifTrue(static fn ($v) => !(empty($v['agent']) xor empty($v['service'])))
-                                            ->thenInvalid('Either "agent" or "service" must be configured, and never both.')
+                                            ->ifTrue(static function ($v) {
+                                                $count = 0;
+                                                if (!empty($v['agent'])) {
+                                                    ++$count;
+                                                }
+                                                if (!empty($v['service'])) {
+                                                    ++$count;
+                                                }
+                                                if (!empty($v['platform'])) {
+                                                    ++$count;
+                                                }
+
+                                                return 1 !== $count;
+                                            })
+                                            ->thenInvalid('Exactly one of "agent", "service", or "platform" must be configured.')
+                                        ->end()
+                                        ->validate()
+                                            ->ifTrue(static function ($v) {
+                                                return !empty($v['platform']) && empty($v['model']);
+                                            })
+                                            ->thenInvalid('When "platform" is configured, "model" must also be provided.')
                                         ->end()
                                     ->end()
                                 ->end()

src/ai-bundle/src/AiBundle.php

@@ -27,6 +27,7 @@
 use Symfony\AI\Agent\Toolbox\Attribute\AsTool;
 use Symfony\AI\Agent\Toolbox\FaultTolerantToolbox;
 use Symfony\AI\Agent\Toolbox\Tool\Agent as AgentTool;
+use Symfony\AI\Agent\Toolbox\Tool\Platform as PlatformTool;
 use Symfony\AI\Agent\Toolbox\ToolFactory\ChainFactory;
 use Symfony\AI\Agent\Toolbox\ToolFactory\MemoryToolFactory;
 use Symfony\AI\AiBundle\DependencyInjection\ProcessorCompilerPass;
@@ -637,6 +638,17 @@ private function processAgentConfig(string $name, array $config, ContainerBuilde
                     if (isset($tool['agent'])) {
                         $tool['name'] ??= $tool['agent'];
                         $tool['service'] = \sprintf('ai.agent.%s', $tool['agent']);
+                    } elseif (isset($tool['platform'])) {
+                        $tool['name'] ??= $tool['platform'].'_'.$tool['model'];
+                        $platformReference = new Reference(\sprintf('ai.platform.%s', $tool['platform']));
+                        $platformWrapperDefinition = new Definition(PlatformTool::class, [
+                            $platformReference,
+                            $tool['model'],
+                            $tool['options'] ?? [],
+                        ]);
+                        $wrapperServiceId = 'ai.toolbox.'.$name.'.platform_wrapper.'.$tool['name'];
+                        $container->setDefinition($wrapperServiceId, $platformWrapperDefinition);
+                        $tool['service'] = $wrapperServiceId;
                     }
                     $reference = new Reference($tool['service']);
                     // We use the memory factory in case method, description and name are set