Codifies what has so far lived in PR closing comments: the universal-
template rule, merge/decline criteria with precedent links, the
feature-complete command bar, the empirical-verification standard,
and the fork path via /add-portal and the community forks discussion.
GitHub auto-surfaces CONTRIBUTING.md on new PRs and issues; README
gets a one-line pointer for browsers.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
