minor #1217 [Agent][Doc] Fix typo (lyrixx)

This PR was merged into the main branch.

Discussion
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[Agent][Doc] Fix typo

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| Docs?         | yes
| Issues        |
| License       | MIT

Commits
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287d5f8 [Doc][Agent] Fix typo

Author: chr-hertel

docs/components/agent.rst

@@ -37,7 +37,7 @@ array of options::
     // Platform instantiation
 
     $agent = new Agent($platform, $model);
-    $input = new MessageBag(
+    $messages = new MessageBag(
         Message::forSystem('You are a helpful chatbot answering questions about LLM agent.'),
         Message::ofUser('Hello, how are you?'),
     );