#779 was happening because environment objects were set on contentView,
which is not the _outmost_ root view. This clarifies why the Theme
object was not being found in ThemeLockScreenModifier.
Also, do not hardcode LogoView as lock view.
Split AppUI into AppUI and AppUIMain to allow for a new, simplified
AppUITV target tailored for the Apple TV.
As a PoC, present a view with a list of the shared profiles.