Introduce (more) README.md / AGENTS.md documentation to the repository.

[georgestephanis]

Right now, the wordpress.org meta repository is a bit of a black box for anyone trying to build on top of it — or orient themselves for the first time. We've got a lot of moving parts (endpoints, directories, forums, Rosetta localized portals, and shared packages) but very little high-level guidance mapping out how these systems tie together.

To make it easier for developers (and AI coding assistants) to propose enhancements without accidentally breaking things, I'd love to see a set of repository-relative markdown guides directly in the codebase.

Why this could help:

• Faster developer velocity: New contributors don't have to guess where plugins or configs live or how to seed a local Docker setup.
• Safer enhancements: Clear guidelines on dynamically deployed files (like the untracked wp-init-ondemand.php) prevent developers and agents from writing broken imports.
• Portability: All links inside the documentation use repository-relative paths, meaning they render perfectly right on GitHub or in any standard viewer.

[georgestephanis]

Files in the PR:

• README.md (Root): An entry point mapping out the folder layout of the Git repository, summarizing the services under active development, and pointing directly to subproject guides.
• AGENTS.md (Root): A developer guide to conventions and internals. It documents key patterns — like dynamic wp-init-ondemand.php bootstrapping, multisite object cache blog prefixing, and SSO client routines — and highlights linting and testing rules.
• api.wordpress.org/README.md: A breakdown of core API routes (browser and version checks, community events feeds, translations) and the Composer v2 package repository logic.
• wordpress.org/README.md: A map of custom plugins and themes (such as the Plugin/Theme Directories, the HelpHub docs layout, Rosetta, and the Gandalf zip scanner).
• common/README.md: Outlines shared dependencies like single sign-on modules and Slack announcement webhooks.
• .github/README.md: Documents the automated CI workflows (the branch-based PHPCS branch check, local Docker wp-env setups, and the co-author Props Bot).

Thanks @georgestephanis! I pushed a few changes and clarifications on things that I noticed.

I'm in favor of having an AGENTS.md (and claude equivalent), so I'm glad that's part of the PR. The details I'm a bit more skeptical of, like all three items in the "Architectural Patterns & Conventions" section. Why the focus on these three, which seem pretty specific and not really reflecting patterns? "Deep-Dive Integrations & Internals", is that something agents _need_ to know about in every session? Things of that nature.

For the READMEs: I think the ones in the repo root and in .github/ are useful and worth iterating on and giving them more meat.
The three subdirectory READMEs (api.wordpress.org, common, wordpress.org) are where I'm less sure. A lot of the content restates what the directory names already tell you ("photo-directory powers the photos registry") and I worry that they'll just get outdated quickly since they mostly just recount the directories. Maybe we could just drop those. Curious what you think?

I'm personally in favor of the subdirectory readmes, as I've found when navigating the repository it can be nice to have that context loading up automagically as you navigate -- like when clicking around in ​https://github.com/WordPress/gutenberg/tree/trunk/packages for example (which is the first repo that kinda got me on the pattern of it).

I'd agree if they'd provide context and non-obvious information, like in your example, but at the moment they're mostly just listing files and directories.

My big want is to get something in. If you'd rather do a thinner addition, I'm fine dropping stuff -- you have a lot more experience than I do in this repo.

Sounds good! Let's drop the readme's in api.wordpress.org, common, and wordpress.org for now and get the rest in as a first pass

Pushed ade2bf60c: dropped the READMEs in api.wordpress.org, common, and wordpress.org as discussed, and updated the root README's workspace map to remove the now-dead links. This should be good to go as a first pass now.

[obenland]

Fixed in [14999].