ci: hugginface space, move from docker to gradio sdk v5.6.0, add missing packages.txt with ffmpeg, pre-requirements.txt with pip, update gradio app to properly format informations to frontend, update tests

feat: first working gradio fronted with refactored lambda_handler and tests

feat: support pytorch and torchaudio, update test, add requirements-dev.txt

test: update python backend test coverage, remove some unused classes and functions (see README.md)

feat: substitute sample table selection with direct input, update TestDataset tests

test: update tests for python 3.10

test: add e2e test TestGetAccuracyFromRecordedAudio

feat: use structlog to handle logging, add some logs

test: start updating tests

refactor: organize project with tests in a package, start following suggestions from pycharm, sonarlint and snyk