App 2.23.1: Retro style also in the accent colour

"Retro (accent colour)" draws the display in the chosen paint colour
and the labels in its light shade; regeneration stays green, a low
battery turns amber. Listed under Retro. Emulator only.

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

SPECS.md

@@ -131,6 +131,12 @@ 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).
+- 2026-10-24 — App 2.23.1 (branch `styles-retro-future`): "Retro (accent colour)", the Retro
+  style in the chosen paint colour — display in `evAccent`, labels in `evAccentLight`;
+  regeneration stays green, a low battery turns amber (not red, so it never looks like Dynamic
+  Red). Same `RetroView`, `setAccentPalette`; listed under Retro, stored as `RETRO_ACCENT`.
+  Checked on the emulator in Dynamic Red with sample values
+  (`screenshots/nilsmg4-2.23.1-retro-accent.png`). Not tried on the car.
 - 2026-10-24 — App 2.23.0 (branch `styles-retro-future`): two more Overview styles, each one
   Canvas view fed a `ClusterValues` per reading. **Retro** (`RetroView`): an 80s digital cluster
   as a vacuum fluorescent display — slanted seven-segment digits (`SevenSegment`, unit-tested)