- Add S24_3LE (S243LE) to format priority list as first choice
- Implement S24_3LE write handler with 3-byte packed conversion
- Add S24LE write handler (was missing explicit implementation)
- Reorder format priority: S24_3LE > S32LE > S24LE > S16LE > FloatLE
This fixes bit-perfect playback on USB DACs that only support
the S24_3LE format (SMSL, Topping, Fosi with TAS1020B chip).
Closes#30
cc
vicrodh
4670b1548a