Settings redesign: cards with focusable rows, segmented controls, gear button

- Settings page follows the Google TV pattern: Konto / App / Handy-
  Fernbedienung cards, each row a full-width focus target with label,
  subtitle and trailing value.
- Quelle and Stream-Qualität are segmented controls switched with
  left/right inside the focused row (click cycles).
- Account row with initial avatar, Abmelden as red row, update row
  with version badge; Update installieren only when one is available.
- Top bar: drawn gear icon button replaces the text pill.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

app/build.gradle.kts

@@ -12,8 +12,8 @@ android {
         applicationId = "dev.castarr.tv"
         minSdk = 26
         targetSdk = 35
-        versionCode = 12
-        versionName = "0.6.1"
+        versionCode = 13
+        versionName = "0.7.0"
     }
 
     // Release signing from environment (see ~/.keys/castarr-release.env on the