fix: update ToolDefinition Javadoc link to correct path

Author: brunoborges

src/site/markdown/advanced.md

@@ -66,7 +66,7 @@ var session = client.createSession(
 ).get();
 ```
 
-See [ToolDefinition](apidocs/com/github/copilot/sdk/ToolDefinition.html) Javadoc for schema details.
+See [ToolDefinition](apidocs/com/github/copilot/sdk/json/ToolDefinition.html) Javadoc for schema details.
 
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