Consider adding Vosk backend

[Erudition]

https://github.com/alphacep/vosk-api/

This project has a libre, offline-capable speech recognition engine that's over 90% accurate - perfect for autoedit!

Vosk is a speech recognition toolkit. The best things in Vosk are:

Supports 20+ languages and dialects - English, Indian English, German, French, Spanish, Portuguese, Chinese, Russian, Turkish, Vietnamese, Italian, Dutch, Catalan, Arabic, Greek, Farsi, Filipino, Ukrainian, Kazakh, Swedish, Japanese, Esperanto, Hindi. More to come.
Works offline, even on lightweight devices - Raspberry Pi, Android, iOS
Installs with simple pip3 install vosk
Portable per-language models are only 50Mb each, but there are much bigger server models available.
Provides streaming API for the best user experience (unlike popular speech-recognition python packages)
There are bindings for different programming languages, too - java/csharp/javascript etc.
Allows quick reconfiguration of vocabulary for best accuracy.
Supports speaker identification beside simple speech recognition.

[pietrop]

I'd welcome a PR if there's interest in adding this, and could provide some guidance on where to
extend the code if there's stil interest in this.