Fix http server priority, improve Ethernet performance.
Switch back to polling I2C to fix led issues.
Show analyzer level in reference units by default.
Support for 96000 kHz and 192000 kHz sample rates.
Fix crash: if processing thread destroyed itself, main thread could
still try to suspend it if interrupted by M0 core. Task state was no
longer valid, and vTaskSuspend would crash.
Use floorf() instead of double emulation variant floor().
Default to 48000 kHz sample rate.