Whisper.cpp compatible /inference STT endpoint

[kth8]

I have many scripts that use whisper.cpp server POST /inference endpoint for transcription. All the mlx_audio.server endpoints available right now are for TTS. I would like to suggest adding a /inference or similar endpoint so STT models like the new Parakeet family added in mlx-audio v0.2.0 can be used remotely.

https://github.com/ggml-org/whisper.cpp/blob/master/examples/server/README.md