Ipyelk

- restore license files

- improve type hints

- Support `pydantic >=1,<3`

- Update dependencies `elkjs 0.9.3`, `sprotty 1.3`, `jupyterlab 4.2`
- Add shim for `reflect-metadata` vs `fast-foundation`

- Migrated to `ipywidgets >=8.0.1,<9`
- Added simple visualizer widget for the diagram pipe status.
- Fixed edge parent ownership affecting self edges ([101])

[94]: https://github.com/jupyrdf/ipyelk/issues/94
[97]: https://github.com/jupyrdf/ipyelk/issues/97
[101]: https://github.com/jupyrdf/ipyelk/issues/101