[FEATURE] Add RTSP variant of GE Proton to the supported types

[ToasterUwU]

It would be awesome if i can also download https://github.com/SpookySkeletons/proton-ge-rtsp from this tool.

Its a Proton Version based on GE, modified to make RTSP Streams in Games work.
This is technically not specific to one Game, but it is most commonly used for VRChat, since there are lots of Video Players in VRChat that use RTSP and are just broken without this specific proton version, either black screen and no sound or worst case the world/game crashes.

[Vysp3r]

I will look into that this weekend while also updating ProtonPlus for GNOME 46.

[Vysp3r]

I will work on adding that tonight and push an update right when I am done.
The migration to GNOME 46 runtime is done and I started implementing your request already.
It should be ready before I go to sleep.