Signing config reads from keystore.properties (gitignored).
Release build has minification enabled. The keystore and
properties file are excluded from version control.
To build a signed release APK:
./gradlew assembleRelease
Output: app/build/outputs/apk/release/app-release.apk
Initial project structure with manifest configured for foreground
audio service, AudioTrack-based playback, and background operation.
Includes Gradle wrapper, dependency catalog, placeholder icons,
and build instructions for Arch Linux.
