Feature request: AsyncOperation jobHandle.WaitUntilComplete()

The job system is brilliant but for non ecs projects that want to yield the completion of some job (or jobs if dependancies were set up) an extention to JobHandle which returned an async operation would be perfect for jobified code intended to run for even up to a few seconds. Bonus points for if the progress can be checked on using AsyncOperation.progress.

Unity likely won't take this on but does anyone have any idea of how to extend this manually? I wouldn't mind having a go at this myself but I wouldnt know where to start.

I have my own package registry I can host on too so others can pull the package if I pull it off!