feat: Spotify support

[aquelemiguel]

Closes #50.

Aims to integrate with already existing code for YouTube playback. Under the hood, it fetches metadata from the Spotify link, builds a relevant query and feeds it to yt-dlp search function.

Tasks

• Reply with warning if environment variables are missing
• Minimize unwraps in spotify.rs
• Investigate alternatives to lazy_static! and simplify ClientError init
• Reply with warning if user submits a private playlist
• Reply with warning if user submits an invalid Spotify link
• Add pkg-config back to the Dockerfile

Screenshots

Success

Failed to authenticate with Spotify

Failed to fetch track/album/playlist

Failed to fetch private/algorithm playlist

[afonsojramos]

It seems that some of the packages that you added made it so that it requires the pkg-config package again. You just need to add it back to the Dockerfile of the build image.

[joao-conde]

Tag me back for review when your tasks are completed

[afonsojramos]

Looking good, just need to clear the submitted discussions and then I will approve!

[joao-conde]

Partial review

[afonsojramos]

Looking good, the .enumerate()/i == 0 changes indeed simplify the code!