Tags

Highlights:

- Added an apptainer directory with the container definition file.
- Added README_CONTAINER.md with container build and usage instructions.
- Added RELEASE.md.
- Added CONTRIBUTING.md.
- Added automated documentation build, container image publishing.
- Added a build-deploy-python-package stage to publish packages to the GitLab Package Registry.
- Improved CMakeLists.txt documentation and migrated to scikit-build-core.
- Added in pyproject.toml the needed dependencies.