Fixed buttons in subscription groups and made select button click only work when there are things selected.

Fixed Rumble channel contents having empty author. Changed TutorialVideo so author is not clickable.

This reverts commit 1dc6eee2.

Added icon based on the system key when a polycentric user has not set a profile picture. Made managing Polycentric profile most robust. Fixed an issue where latest events were not always being shown in relation to Polycentric profiles. Added copyable (on long press) system key in Polycentric profile activity. Added tutorial videos tab and flow.

Progress bars subscription groups, Various notification permission requests, improved notification experience, Settings activity open to specific settings, refs

Fixed duration format. Added tutorial fragment. Added dialog that asks you if you want to see the tutorials on the first app boot. Made casting when clicking start now open connected dialog. Fixed crashes related to sliders in casting connected control. Fixed history tab title. Removed old FCast encryption.

Added support for FCast encrypted connection upgrade and added support for ensuring threads are restarted onResume for FCast and ChromeCAst.