The VPS had no /opt/staging directory or compose file, causing the deploy
step to fail with "No such file or directory". Now the workflow:
- Creates /opt/staging if missing
- Writes compose.yml on every deploy (keeps it in sync with CI)
- Touches .env so podman compose doesn't error if no secrets file exists yet
Also adds deploy/staging/.env.example documenting runtime secrets that must
be set manually on the VPS after first deploy.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
