Reorganize std docs so that they follow the same tree structure that the std crate does

[jfecher]

Problem

Organization of functions & other items in the standard library docs for Noir is arbitrary.

Happy Case

The organization should mimic the actual modules in the std crate itself. This will also give a better idea to users on how the stdlib is structured.

For bonus points these docs could be autogenerated from doc comments on stdlib items.

Workaround

None

Workaround Description

No response

Additional Context

No response

Project Impact

None

Blocker Context

No response

Would you like to submit a PR for this Issue?

None

Support Needs

No response

[asterite]

I'd really like us to have auto-generated docs, and docs when hovering over items.

My idea, to begin with, was this:

1. We start producing the doc comments in the lexer, but only when needed (if in LSP mode, or if generating docs (which we currently don't have, but...))
2. We consume doc comments before items that could have doc comments (modules, structs, functions, etc.).
   a. That means that a doc comment in an unexpected position will produce an error... maybe that's fine? It seems Rust works that way too.
3. We store those doc comments as a vector of strings, unprocessed, likely in NodeInterner
4. In LSP, when hovering over an item, or when suggesting autocompletion, we fetch any doc comments attached to an item, concatenate them, and show the result as markdown

At least doc comments will start showing up in the editor. Once that's done we can start working on a doc generator (not sure if there's something we could reuse for actually presenting the docs once we process them).

I'd be happy to work on this in parallel to the other stuff 😄

[jfecher]

Sounds good to me. I'm not sure how much work we'd save by only saving doc comments if we're in lsp mode or generating docs but the plan sounds sensible.