YAML metadata with string containing hyphen breaks building

[henrikvilhelmberglund]

YAML metadata with string containing hyphen breaks building. For example I had a .md file generated from Obsidian with excalidraw-plugin in its own frontmatter, this caused mdsvex to try and parse it which caused an error because const { excalidraw-plugin } isn't valid JS.

I then tried to change the frontmatter string to something else with this

frontmatter: {
		marker: "+",
	},

but that also caused building to fail.

I'm guessing dashes could just be replaced with "" and things should work.
Code is somewhere here:
https://github.com/pngwn/MDsveX/blob/master/packages/mdsvex/src/transformers/index.ts#L335