4peace1/spooty ? reverse-engineered prompt

Build me a self hosted web app called Spooty that lets me paste in a Spotify track, playlist, or album link and download the matching songs to my server. It should also let me subscribe to a playlist or artist page so it can check for new releases and grab them automatically later.

I want it to run nicely in Docker, expose the app on port 3000, and save downloads to a folder I can mount from outside the container. It should also support a cookies file for YouTube downloads when needed, since some content may be restricted.

Please make the setup straightforward, with a simple web interface, a backend that handles the downloads and a database for saved items and subscriptions. Use current docs online if you need to, and keep the defaults safe so it does not hammer YouTube too hard.