Previously, `docker image prune` ran immediately after deploying new
containers, potentially deleting the old images needed for rollback
if smoke tests subsequently failed. Now the deploy pipeline:
1. Tags current images as :rollback before pulling new versions
2. Only runs `docker image prune` after smoke tests pass
3. Uses explicit :rollback tags for rollback instead of relying on
Docker layer cache (which is fragile)
Applied to:
- scripts/deploy-production.sh (manual deploy script)
- .github/workflows/deploy.yml (staging + production CI jobs)
- docs/deployment.md (updated rollback documentation)
Co-Authored-By: Paperclip <noreply@paperclip.ing>