[audio] Add logging/metrics for playback hardening

Notify AudioService when a track encounters playback hardening for
metrics/app debugging/logging purposes.

The enforcement may be exempted for certain reasons (such as usage), but
ensure that we log anyways for metrics/visibility so we can chase down
exemptions.

We only dispatch this notification once per track instance for more
useful metrics and to avoid log spam.

Test: atest android.virtualdevice.cts.audio.VirtualAudioTest manual log
verification
Test: oboetester silenced audio manual log verification
Bug: 376481063
Flag: com.android.media.audio.hardening_impl

Change-Id: I9c76f7e5691a518461a8d002f08cd0e7c88ebd5c