Every push and pull request installs, tests and builds the game. Pushes
to main then ship the sources to the server over SSH and restart the
site with docker compose; the deploy step is skipped until the
DEPLOY_HOST / DEPLOY_SSH_KEY secrets exist. An optional HEALTH_URL is
polled after deploying.
The Gitea server is now the `origin` remote; GitHub remains as `github`.
Gitea ignores .github/workflows while .gitea/workflows exists, so the
GitHub Pages workflow keeps running only on GitHub.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
