bug #171 [MCPSDK] Make content an array to match the MCP spec (tom-hart-sky-uk)

This PR was merged into the main branch.

Discussion
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[MCPSDK] Make content an array to match the MCP spec

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  |no <!-- please update src/**/CHANGELOG.md files -->
| Docs?         | no <!-- required for new features -->
| Issues        | Fix #123
| License       | MIT

Force `content` in `\Symfony\AI\McpSdk\Server\RequestHandler\ToolCallHandler` to be an array to match the [spec](https://modelcontextprotocol.io/specification/2025-06-18/schema#calltoolresult-content)
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Commits
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15320d2 Make content an array to match the MCP spec

Author: chr-hertel

src/mcp-sdk/src/Server/RequestHandler/ToolCallHandler.php

@@ -60,7 +60,7 @@ public function createResponse(Request $message): Response|Error
         };
 
         return new Response($message->id, [
-            'content' => $content,
+            'content' => [$content], // TODO: allow multiple `ToolCallResult`s in the future
             'isError' => $result->isError,
         ]);
     }