Update and render on remaining time changes

[christoph-heinrich]

Pausing a live stream leads to the remaining time changing without any actual playback, but so far the UI would only update the remaining time when the playback time changed.

[FichteFoll]

Thanks for these various qol fixes. Some of these like this have also bothered me for a while, but not enough to spent the time working myself into the code base to fix them (or even reporting them, now that I think of it).