Replace generic system icons (info bubble, stock alarm clock) with a
custom equalizer-bars vector drawable across all 4 notification
builders: pre-notice, snooze countdown, ringing alarm, and the audio
player. Apply the app's cyan brand color to the 3 alarm notifications
that previously had none. Audio notification now explicitly declares
its icon instead of falling back to the full-color launcher icon,
which Android was auto-silhouetting into an illegible status-bar
blob.
