The signed-out screen was a `VerticalLayout { alignment: center }` with
no scroll. That was already tight with two routes; the folder option
made the column taller than a 900x560 window, and a centred layout that
overflows clips at *both* ends — so the masthead and the last route
disappear together, with nothing on screen to suggest either existed.
A Flickable whose viewport follows the content, and a top padding that
centres the column only while it fits. Both cases checked against the
running app: centred at 1000x1800, top-aligned and scrollable at
900x560.