The Gitea Actions runner is a container; it can't see host paths.
The dostalgia compose dir is mounted inside the runner at /unraid/dostalgia,
so that's what the workflow must reference.
Uses docker compose -f /appdata/dockhand/stacks/unraid/dostalgia/compose.yaml
so the container matches the user's Unraid stack configuration (correct volume
mount at /mnt/cache/appdata/dostalgia, proper network, labels, etc.)