Safeload mixer/EQ/master on the ADAU1701, persist AudioProfile in NVS, expose /api/audio routes and web UI controls, with host tests and manual sync. Co-authored-by: Cursor <cursoragent@cursor.com>
Introduces Si4684/ADAU1701 drivers, TunerService, FrequencyKHz, SeekDirection, /api/tuner routes without file-scope globals, host tests, and firmware blob tooling (binaries remain gitignored). Co-authored-by: Cursor <cursoragent@cursor.com>