spotdl/spotify-downloader — reverse-engineered prompt

Build me a simple Python app that lets me paste Spotify song, album, or playlist links and download the tracks by finding the best matches on YouTube. I want it to save the audio files with clean metadata, album art, and lyrics when available, and make it easy to run from the command line with sensible defaults.

It should also support saving playlist info without downloading, generating friendly source URLs, updating tags on existing files, and syncing a local folder to a playlist so new songs get added and removed ones get cleaned up. If possible, include a lightweight web mode for downloading single songs too.

Please make setup straightforward, including checking for or helping install FFmpeg and Deno since some downloads depend on them. Keep it polished, accurate, and easy for a normal person to use. Look up current docs online if you need to.