Support for Markdown Frontmatter parsing (`.md` and `.mdx`)

[pattobrien]

Thanks for the awesome page!

It'd be awesome if we could support frontmatter validation within .md and .mdx files.

Some example use cases:

• validating Claude Code Slash Command frontmatter (link)
• parsing astro layout metadata (example)
• validating Cursor .mdc files (link)
• Obsidian notes metadata (link)

After getting some initial thoughts, I'd be happy to open a PR!

[ota-meshi]

Thank you for posting this issue!

I think this will become possible when @eslint/markdown is able to use a processor to lint the frontmatter as a code fragment.
(Currently, it seems to only support code blocks.)

How about making a request to @eslint/markdown to enable linting of frontmatter?