fix: use docblock description instead of summary

[markhuot]

The summary is only the first line of the docblock. In many cases you need more than a single line to describe your tool adequately to the LLM. Using the description will return the first line plus all other lines until the parameter definitions.

Alternatively we could make manual tools support the #[McpTool(...)] annotation?

[Copilot]

Pull Request Overview

This PR changes how tool descriptions are extracted from docblocks by using the full description instead of just the summary. This allows tools to have more comprehensive descriptions for LLMs, as the summary is limited to the first line while the description includes all content until parameter definitions.

• Replace getSummary() with getDescription() when extracting tool descriptions from docblocks

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}