SPECS: CarPlay's 1920x640 is hard-coded in Allgo's system app; ignore dump/

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LhzAVaUyqcw5PkGjz4mWW6

SPECS.md

@@ -118,6 +118,15 @@ tyre pressures, GPS (lat, lon, elevation, heading) and the is_* flags. It does *
   confirmed car facts, app structure, UI conventions, build/test/ship, documents. It replaces
   upstream's EVABRPUploader text. The test emulator is now in the flake: `nix run .#car-emulator`
   (Android 9 AOSP at 1920×720, 160 dpi; the car build installs as the system user — checked).
+- 2026-10-23 — CarPlay full screen: not possible on this firmware (SWI68). The export from the
+  car showed CarPlay's window at 1920×720 with both SAIC bars hidden (policy_control on), and its
+  video SurfaceView at (0,80), 1920×640, with a 1920×640 buffer: the grey strip is the window's own
+  background above the video. Allgo's `/system/app/AllgoCarplay_EH32` hard-codes it twice:
+  `CarPlayService` announces `SCREEN_HEIGHT = 640`, `SCREEN_WIDTH = 1920` to the iPhone (it reads
+  `sys.screen.heightpixel/widthpixel`, then overwrites them with the constants), and
+  `carplay_screen_layout.xml` places the SurfaceView at `640px` high with `80px` top margin. Both
+  are in the read-only, signed system image. The export (`dump/`) is gitignored: it holds Allgo's
+  software.
 - 2026-10-23 — App 2.19.5: installing from USB (and over the air) works on the car again, with a
   confirmation. The update log showed the car refusing the silent session: `Not allowed to install
   non-system apps on internal storage`. The fallback, Android's installer screen, then said "There