feat: add chain wrapper tool (#266)

Author: chr-hertel

src/Chain/Toolbox/Tool/Chain.php

@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpLlm\LlmChain\Chain\Toolbox\Tool;
+
+use PhpLlm\LlmChain\ChainInterface;
+use PhpLlm\LlmChain\Model\Message\Message;
+use PhpLlm\LlmChain\Model\Message\MessageBag;
+use PhpLlm\LlmChain\Model\Response\TextResponse;
+
+final readonly class Chain
+{
+    public function __construct(
+        private ChainInterface $chain,
+    ) {
+    }
+
+    /**
+     * @param string $message the message to pass to the chain
+     */
+    public function __invoke(string $message): string
+    {
+        $response = $this->chain->call(new MessageBag(Message::ofUser($message)));
+
+        assert($response instanceof TextResponse);
+
+        return $response->getContent();
+    }
+}