[Feature request] Isolate gamepad/joypad/gaming controllers

[clsty]

From README:

Note that this does not allow multi-seat gaming using controllers, as these are not isolated. It might allow some form of multi-seat gaming using keyboard and mouse since these input events are "injected" into the compositor session.

However maybe it's possible to isolate gaming controllers by using a similar approach mentioned in games-on-whales/wolf#193 (comment)

[hgaiser]

I like the idea, if you want to try it out and perhaps submit a PR that'd be welcome :).