Replaces default debug signing with a dedicated release keystore loaded via android/key.properties. Fixes the cross-host signature mismatch that broke adb install -r. keystore and key.properties are gitignored (signing identity must not be committed).
Co-Authored-By: Claude <noreply@anthropic.com>
Integrate audioplayers, vibration, and file_picker packages to provide
audio/haptic feedback on registration success/failure. Add sound
settings UI in SettingsPage for customizing notification sounds.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>