AppExit should be an observer event rather than a BufferedEvent #20408
Description
What problem does this solve or what need does it fill?
Multiple AppExit events in a buffer doesn't make sense, and would be better modeled as an observer event. This would be more performant for plugins to react to app exits, rather than having to schedule a system that runs every frame.
What solution would you like?
Swap AppExit to an observer event.
What alternative(s) have you considered?
Weird status quo.