Prettier is the closest thing I've found, even if it's primarily targeting Javascript. My biggest gripe is the dependencies that it ships with. I'd love to find a static binary that can accomplish the same thing. Any suggestions?
I think a non-code formatter could be a good idea though. Particularly normalising over the various dialects of Markdown.
If it doesn't exist, perhaps you should build it yourself? The easiest way to build a CLI tool as a static binary is probably with Go, although I'm not a big fan of the language. Perhaps this could be a chance to try your hand at Rust.