Add documentation generator

[kevaundray]

Problem

Similar to rust-doc it would be helpful if Noir could have doc comments and a way for those to be exported such that they can be ingested by other tools.

To-do

• Investigate the different ways to have something akin to rust-docs/doxygen

[Savio-Sou]

Let's convert this into Issue(s) when we can narrow it down into action item(s).

[Savio-Sou]

Converted into #3362.