stack nav for iOS/iPadOS

[heckj]

After using the alpha app on iOS and iPadOS a bit, it's clear that I don't get a choice about being embedded within a NavigationView when I'm using a DocumentGroup style app. So any view implementation on those devices needs to account for the top-space consumption. Additionally, on iOS there's just insufficient vertical space to make any meaningful progress on viewing a stored search or ranking a search that's been stored.

It's clear that I need to just bite the bullet and engage NavigationView (aka StackNavigation in future iOS versions) and deal with the navigation as expected.