Untracks envs/rex/.env and envs/siong/.env (kept on disk so existing
deploys keep working) and adds matching .env.example templates so a
fresh clone has something to copy from. .gitignore widens from
envs/dev/.env to envs/*/.env to cover all three deployments.
Per-deployment secrets are no longer committed; rotation deemed
unnecessary because the repo is hosted on a private self-hosted Gitea
instance.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>