GET api/track/waveform-status and POST api/track/{id}/waveform (ApiKey);
CmsTrackService methods; TrackPreProcessing page with per-row and
sequential bulk generation; nav links from TrackList and Index.
ILoudnessAlgorithm strategy (RmsLoudnessAlgorithm first impl), WaveformProfileService
stores quantized byte[] sidecar in new MediaFileVault (profiles vault), wired into
UnifiedTrackService.UploadAsync; failure is logged and swallowed. WaveformProfileDto
and WaveformProfileOptions in shared projects.