Tvb-widgets

A new feature has been added to the PhasePlaneWidget to allows users export a model configuration into JSON or PYTHON format.
Fix bug in TimeSeriesWidget to display channel values when SV/mode has been changed.

- include `package.json` into the distribution pack

- fix `numpy` bug
- include `requirements.txt` into the distribution pack

Fix bug of not including the `.css` file for `ipyreact` based widget.

**Release notes - EBRAINS2.0 - w2.0**
**Story**
[EBR-23](https://tvb-projects.atlassian.net/browse/EBR-23) Create a DICOM Widget

**Bug**
[EBR-29](https://tvb-projects.atlassian.net/browse/EBR-29) tvb-widgets not working in JupyterLab 4

[EBR-33](https://tvb-projects.atlassian.net/browse/EBR-33) upgrade ipywidgets lib in tvb-widgets

[EBR-34](https://tvb-projects.atlassian.net/browse/EBR-34) delay in showing changes in control features - 3D Connectivity Widget

[EBR-35](https://tvb-projects.atlassian.net/browse/EBR-35) Jupyter Lab crashes while running Connectivity notebook

**Task**
[EBR-16](https://tvb-projects.atlassian.net/browse/EBR-16) More options to visualize data

[EBR-19](https://tvb-projects.atlassian.net/browse/EBR-19) Release Connectivity widget with iPyReact

[EBR-24](https://tvb-projects.atlassian.net/browse/EBR-24) Mirror tvb-* relevant repos under EBRAINS 2.0 gitlab