Support 360° footage

[hybridherbst]

It would be great if we could support more types of footage out of the box.
Currently, we only support DomeMaster 1:1 aspect footage.

However, we could probably detect the intended format by looking at the aspect ratio, and e.g. assume that 2:1 video is equirectangular 360° video footage, and then show the top half of that (or provide playback options).

Additionally, there's 180° formats like the ones produced by Vision Pro, where it would be interesting to check if we can at least provide guidance on how to reformat it for Dome playback.