BREAKING CHANGE: analytics_podcasts_by_player table and analytics_podcasts procedure were updated

feat: add lock podcast according to the Podcastindex podcast-namespace to prevent unauthozized import

replace platform visible checkbox with switch

- intl NumberFormatter doesn't work as it should with french language
- fix typo in episode french tranlation

fixes #64

- add .editorconfig file
- format all files to comply with castopod's coding style
- switch parsedown dependency with commonmark library to better follow commonmark spec for markdown
- add prettier command to format all project files at once

closes #16