[PP-5] Documentation for code components

Decrementing PP in issue title since hydration library got in

Oh looks like other blockers are also done now, so updating again to reflect

✨ Create a ComponentSource plugin for JS components Active updated docs/components.md (for the js ComponentSource plugin) and docs/config-management.md (for the JavaScriptComponent config entity).

Unfortunately, ✨ Storage for global CSS Active did not update docs/config-management.md (for the AssetLibrary config entity), so that still needs doing here.

Follow-up to #6: ✨ Loading and auto-saving an edited code component Active brings two crucial changes to the AssetLibrary config entity worth documenting:

1. A global AssetLibrary is created during installation, with empty CSS and no JS.
2. The library_info cache tag is automatically invalidated when saving any AssetLibrary config entity, causing all asset library info across all extensions to be recomputed: https://git.drupalcode.org/project/experience_builder/-/merge_requests/6...

@effulgentsia came up with a way to patch Astro's code in our bundled hydration library (done in ✨ Hydration library for code components Active ), and introduce our own type identifier, raw, that allows us to pass values where Astro will work with the value as is. Alex also opened this PR for Astro: https://github.com/withastro/astro/pull/13046.

— issue summary of 🐛 Fix code component prop serialization in Astro islands Needs work .

On that PR:

Right now, while we have no specific plans to change the format, we can change it at will without worrying about breaking any other implementation. If you’re manually constructing islands, there’s a risk that it would break in a patch release. Realistically you’d need to be responsible for checking yourself that there are no breaking changes in the format in new releases.

— https://github.com/withastro/astro/pull/13046#issuecomment-2609036184

This seems pretty essential to document!

Another MR that landed that merits being documented: the way that import_maps work. See #3507567-12: Make JS files generated from code components import Preact modules with the correct paths → for the high-level architecture on the "integrate with existing Drupal infra" side.

Another essential piece to document: ✨ Bundle a small selection of packages in the hydration library for code components Active .

We now have packages that can be imported:

import { cva } from "class-variance-authority";
import { clsx } from 'clsx';
import { twMerge } from 'tailwind-merge'
import { cn } from "@/lib/utils";

Where cn() is this function:
https://git.drupalcode.org/project/experience_builder/-/blob/f3b8c6279c2...

This must happen in the current sprint.