* refactor localWhisper to use new custom FFMPEGWrapper class
* stub tests in github actions
* add back wavefile conversion to 16khz 32f to fix docker builds
* use afterEach for cleanup in ffmpeg tests
* remove unused FFMPEG_PATH env check
* use spawnSync for ffmpeg to capture and log output
* lint
* revert removal of try/catch around validateAudioFile for more helpful error msgs
* use readFileSync instead of createReadStream for less overhead
* change import to require for fix-path and stub import in tests
* refactor to singleton to preserve ffmpeg path
dev build
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Co-authored-by: Timothy Carambat <rambat1010@gmail.com>