There's no reasons for this to be a property of only ArgName::Named to begin with. And now, with the extra indirection introduced for arg_name, it may leads to subtle issues when patterns args are used in validators.
- Add support to the formatter for these doc comments
- Add a new field to `Arg` `doc: Option<String>`
- Don't attach docs immediately after typechecking a module
- instead we should do it on demand in docs, build, and lsp
- the check command doesn't need to have any docs attached
- doing it more lazily defers the computation until later making
typechecking feedback a bit faster
- Add support for function arg and validator param docs in
`attach_module_docs` methods
- Update some snapshots
- Add put_doc to Arg
closes#685