Extracts sign+push logic into a reusable push-nix-cache action.
Both the site deploy and the image build now use it.
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
- deploy-static-site/images/flake.nix: moved from images/flake.nix
- .forgejo/workflows/build-static-server.yaml: moved from images/.forgejo/
(Forgejo only picks up workflows from repo root .forgejo/workflows/)
- updated path reference in build workflow
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
