Replace the Docker buildx + skopeo composite action with a Dagger Python
module for building and publishing container images. BuildKit's native
push is compatible with Zot, eliminating the skopeo workaround entirely.
- Add Dagger Python module (.dagger/) with build/publish functions
- Update build-container.yaml workflow to use `dagger call publish`
- Add Dagger CLI to forgejo-runner image (v0.19.11)
- Bump runner version to v2.6.0 in ExternalSecret
- Add GPLv3 LICENSE
- Add dagger to mise.toml
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>