App 2.8.0: full screen

Immersive full screen while the app is in front: the system's top and
bottom bars are hidden, and a swipe from the edge shows them briefly.
Re-applied whenever the window regains focus. A "Full screen" switch in
the Upload tab (default on) turns it off.

On the Android 9 emulator the bars are hidden (system UI flags 0x1706),
stay hidden after leaving and returning, and the switch toggles them
through the UI. Whether SAIC's own bars on the MG4 obey the flags is
only known on the car; if they do not, nothing changes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QLJfZQZeAKAwSqViTmLzki

SPECS.md

@@ -114,6 +114,9 @@ tyre pressures, GPS (lat, lon, elevation, heading) and the is_* flags. It does *
   INGEST_TOKEN) into git and pushed it. Commit amended and force-pushed; both values regenerated in
   the now gitignored `k8s/secrets.yaml` (since moved to `k8s/secrets/secrets.yaml`, outside
   `kubectl apply -f k8s/`). Filled-in secrets live only there from now on.
+- 2026-10-17 — App 2.8.0: immersive full screen (switch in the Upload tab, default on). Hides the
+  system bars on the emulator; whether SAIC's own bars on the MG4 can be hidden is only known once
+  tried on the car.
 - 2026-10-17 — App 2.7.1: the voice key works. The car's key report, read off the on-screen log:
   `android.intent.extra.hardkey.keycode` (Integer), `.down` (Boolean, a report per press and per
   release), `.longpress` (Boolean). 2.7.0 looked only for short names and never found the code.