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

app/build.gradle

@@ -34,8 +34,8 @@ android {
         applicationId "com.stinnesbeck.nilsmg4"
         minSdk 27
         targetSdk 36
-        versionCode 115
-        versionName "2.23.0"
+        versionCode 116
+        versionName "2.23.1"
 
         // Nothing about the server ships in the APK: its URL and ingest token are entered in
         // the app's Server tab (ServerConfig), and the database is only reachable by the server.