Build workflow: runs tests + assembles debug APK on pull requests.
Release workflow: builds signed APK and uploads to GitHub release.
Signing config reads keystore from env vars (set by CI secrets).
Keystore files excluded from git.
Signed-off-by: Avinal Kumar <avinal.xlvii@gmail.com>
Co-Authored-By: Claude Opus 4.6 (1M context)
