The default view and the month style are now a step each, and both are
built from the same live-preview-over-grouped-rows shape as the Settings
choosers they duplicate, instead of chips. The month style is asked
whatever view was picked — Month is reachable from the drawer regardless,
and making the step conditional would move the counter on the step right
before it.
Back is a button in the step's top bar and the system gesture, both
clearing the previous step's answer; the plan derives position from those
answers, so that is all the navigation there is. The calendar grant has
nothing to return to, so back stops there. The slide runs backwards when
it does.