[TRACKING] Add documentation

[joelhawksley]

Problem

Primer ViewComponents has little documentation. It's difficult for consumers of the library to know how to use it correctly.

Developers looking for documentation expect to find it at primer.style, but their search comes up empty.

Solution

Add a Primer ViewComponents section to primer.style.

TODO

• Test YARD documentation tool (done, see add YARD & docs for CounterComponent #64).
• Build out end-to-end proof of concept for generating markdown documentation from YARD, served by Doctocat.
• Write documentation for all components, using yardstick to ensure complete coverage.
• Ship documentation site on primer.style
• Add Status field for each component like we have in Primer CSS (New, Stable, etc)

[joelhawksley]

Today, @broccolini, @colebemis, @yaili and I chatted about this project. Here are some notes:

TL;DR
We're going to proceed with the current approach (using YARD) to see how documenting more components goes.

Editor integration
@broccolini asked if YARD comments will allow for editor integrations, such as in VS Code. It looks like the solargraph plugin uses YARD comments for this kind of behavior 🎊

Open questions

• How will we build out new components in Primer CSS alongside their ViewComponent equivalents?

[joelhawksley]

Per @kevinsawicki here, let's look at adding an explanation of the Octicon Size values 😄

[kevinsawicki]

Another idea, might be nice to have some small doc about the fundaments of slots. I get search results for them but not exactly what/why/how they are:

[joelhawksley]

Another idea: We should directly link to Storybook for each component.

[manuelpuyol]

@joelhawksley shall we close this?

I think that we reached a very stable docs now, with no missing components and links to Storybook/Code + dark mode

[joelhawksley]

@manuelpuyol agreed!