Add Claude Code project instructions

[ru-sh]

Checks in the guidance Claude Code reads when working in this repository, so it does not have to be rediscovered each session.

CLAUDE.md covers the parts that are easy to get wrong here: the submodule has to be initialized before npm install (postinstall builds its deps), patches are applied with quilt and never edited in lib/vscode directly, npm run test:unit is the default verification while e2e needs a full release build, and build:vscode requires VERSION. It also records the fork conventions — PRs target this repository and squash into main.

Two skills go with it:

• .claude/skills/vscode-patch — the quilt workflow, including that quilt add is mandatory before editing or the change is silently untracked, and that every intermediate state of the stack must still build.
• .claude/skills/e2e — how to build for and run the Playwright suite, and which changes need a full build:vscode versus a fast npm run build.

.claude/settings.json adds one hook that runs the repo-local prettier over files Claude writes, so agent edits do not fail prettier --check ..

🤖 Generated with Claude Code