- TopModeBar widget: persistent pill-shaped header (HTML prototype:
#topBarWrap/#editModeBtn/#flyModeBtn) tinted in the active mode's color,
with the inactive mode offered as a solid button in the corner to switch
into it.
- AppShell now provides a single shared Scaffold + Stack, overlaying
TopModeBar on top of whichever screen (Plan/Fly) is active, instead of
each screen owning its own Scaffold.
- Wired the Fly button to AppModeCubit.toFly(), which enforces the
Ready-to-Fly gate (doc 4.5). Since upload/verify isn't wired up yet, the
gate is never satisfied yet, so tapping Fly now shows a SnackBar instead
of throwing an uncaught StateError.
- Extended the widget test to cover both the bar's presence and the
gate-rejection path (was the source of a real bug: an initial
negative-margin Container hack for the "bleed into the corner" look
violated Container's margin.isNonNegative assertion and crashed the
whole tree - fixed with padding instead).
Verified with flutter analyze, flutter test, and a real run on the
Pixel_10a emulator (visually matches the prototype screenshots in design/,
Fly-tap correctly shows the gate message without crashing or switching mode).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
