Add a `contexts` field to the .md metadata for a custom chat mode

[TheColorRed]

In the new chat mode, it would be nice if I could add some additional contexts to the .md file that would be used with the request so that I don't have to specify them every time I use the chat mode.

---
description: Generate an implementation plan for new features or refactoring existing code.
tools: ['codebase', 'findTestFiles', 'githubRepo', 'search', 'usages']
contexts: ['#codebase', '#my-file.yaml', '#other-file.md', '#my-folder']
---

# My Custom Chat Mode

The is an example custom chat mode