feat: virtualize rendering

[thomasnordquist]

This reduces CPU consumption massivly and allows to display GIANT

• [ ] check that ViewModel is released when no longer used
• [ ] check memory consumption in general
• [ ] fix auto expand (currently everything is expanded, logic needs to move to ViewModel since the react state is lost when component moves outside of viewport
• [ ] fix activity highlighting (blinks more then expected)
• [ ] topic ordering probably needs to be re-implemented in ViewModel

Downside

Scrolling is a bit weird with very long lists, the virtualization has some issues maintaining the scroll index if data is added / removed before the scroll position.