Updates authentication and onboarding layouts to use dynamic viewport height (adding min-h-[100dvh] alongside min-h-screen) to prevent iPad/mobile browser UI from causing scroll and clipping, fixing issues like logos being cut off on signup/onboarding screens. This should improve full-screen layout consistency across devices, but there’s a potential risk of unintended layout/scroll behavior differences across browsers that interpret dvh differently, and the PR currently has a failing api-tests check that should be investigated before relying on the change.