[3.3.x] Apple TV: add media download to web interface, add debug log download to web interface

This cleans the current implementation of the micro media library on Apple TV by moving it to a designated class instead of hosting in a view controller. There are no functional changes besides that all local items on Apple TV will now be played as a list allowing to repeat that list, which was often requested for PoS.

Further, this MR adds media downloads to the Apple TV's web interface to match what we do on iOS and finally adds downloads of debug logs to the web interface. and to prevent cluttering Apple TVs with logs, all of them will be deleted automatically as soon as the user decides to no longer record any.

Backport of !674 (merged)