The loss in durability shouldn't matter, if we can just receive the same
events again after a restart

Conflicts:
	CMakeLists.txt
	io.github.NhekoReborn.Nheko.json
	src/Cache.cpp
	src/timeline/TimelineModel.cpp
	src/timeline/TimelineModel.h
	src/timeline/TimelineViewManager.cpp

Support voice calls

Integrating that in our CI is currently a bit hard, so disable it for
now, if GStreamer isn't found. Just make sure to build against GStreamer
for call support!