Implement project selection page

[astanik]

This issue relates to https://github.com/remsfal/remsfal-frontend/blob/main/src/views/ProjectSelectionView.vue

This page is displayed after login, if no project exists or no project is selected in the topbar.

Minimum requirements for this issue:

• The user receives an overview of the projects
• The user can create a new project
• The user can select a project that will also be changed in the topbar

[FelixSiegfriedRiedel]

Great idea! I would like to work on that :)

[FelixSiegfriedRiedel]

I would implement it like that, using a Sakai table with clickable rows that lead to the respective project page.