Update the Meta Handbook with useful info

[tellyworth]

The Meta Handbook is almost empty and contains little useful info: ​https://make.wordpress.org/meta/handbook/

It needs to be updated to add some current info about what the team does, how to get started, and where to find things.

Let's discuss and collect ideas for what to add in this ticket.

[renyot]

I'm thinking that we can first organize the chapter title.
Now the chapter titles don't give clear instructions as far as I'm concerned.

I'm considering that we can just refer to ​https://make.wordpress.org/core/handbook to make the changes and this is something roughly I have in mind for the chapter title we can change to:

1. About the Meta Team - Introduction to the team. Useful links to both internal and external pages.
   1. Projects (Existing page) - Detailed info about each project of Meta.
2. Getting Started
   1. Contribute with Code
   2. Contribute with Testing
   3. Contribute with Docs
3. Advanced - Some advanced topics.
4. Best practices - Some latest practices we follow or some good advice for contributors.
5. Reference - Links to pages that help contributors know more and deeper about Meta. e.g., Glossary, Events, Schedule, Related Channels, Info/Knowledge reference, etc.

It seems to me that if we could make the goal and definition of every chapter as clear as possible, we can reduce the duplicated content and have a cleaner docs structure for newcomers to follow and contributors to add more stuff. We can spend more time discussing this.

[tellyworth]

Using other handbooks (especially core) as a template is a great idea for getting things started. It would make sense to use a similar structure, and some of the introductory content could be similar.

Rather than discuss everything first and publish later, I suspect it's more productive to start very small and build incrementally on it. We can use this ticket for discussion in parallel.

Those sound like good chapter topics as a starting point. Why not create those pages and headings right away, even if it's with a stub that says something like "see #6286 to help contribute content here".

One thing I'd like to get up there soon is links to all the key repositories. Especially those outside of Trac, like:

​https://github.com/WordPress/wporg-news-2021
​https://github.com/WordPress/wporg-mu-plugins
​https://github.com/WordPress/translate-w-org-env
​https://github.com/WordPress/wporg-repo-tools
​https://github.com/WordPress/wporg-gutenberg
​https://github.com/WordPress/five-for-the-future

and all the other meta-related repos that I've forgotten :)

[tellyworth]

Oh I forgot ​https://github.com/wordpress/learn of course!

The Projects page is probably the best place for those to go: ​https://make.wordpress.org/meta/handbook/about/projects/

As we discussed privately, some of those are deprecated, and others have Trac links where they should instead link to GitHub. We could either put the GH projects in a separate section, or add them to the main table and link to GH instead of Trac for those.

It seems a bit odd for Codex to have its own special "other projects" section. I guess that's because it wasn't ever open sourced(!). Perhaps it would make sense to rename that section "deprecated", and move the old unmaintained projects in there.