minor #60 docs: fix build (OskarStark)

This PR was merged into the main branch.

Discussion
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docs: fix build

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

Commits
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940b8e3 Fix: RST

Author: OskarStark

src/platform/doc/index.rst

@@ -134,7 +134,8 @@ This provides several benefits:
 - **Timestamp extraction**: Get the exact creation time from the ID
 - **Database-friendly**: Sequential nature improves index performance
 
-.. code-block:: php
+::
+
     use PhpLlm\LlmChain\Platform\Message\Message;
 
     $message = Message::ofUser('Hello, AI!');