About dialog points to our repository; SPECS status refreshed

The About dialog's link and QR code open
https://git.stinnesbeck.com/nils/mg4 instead of Fatih's GitHub
repository (the credits to upstream stay). SPECS.md: the Status section
describes the current versions and what has and has not been tried on
the car; the architecture notes list the current tabs and data paths.

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

app/build.gradle

@@ -34,8 +34,8 @@ android {
         applicationId "com.stinnesbeck.nilsmg4"
         minSdk 27
         targetSdk 36
-        versionCode 80
-        versionName "2.14.2"
+        versionCode 81
+        versionName "2.14.3"
 
         // 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.