Feature/ like-save songs

[ashikvarma11]

What I did so far

• Added API calls for fetching saved-tracks, add and remove saved-tracks from the user's library.
• Added 💚 icon for like/save. Toggling adds/removes tracks from the user's library.
• Added ❗ icon for tracks where the preview is not available.

TO DO

• Log in checks while saving a track.

[ashikvarma11]

@rtkg12 Please guide me through the login checks.

[rtkg12]

Hey @ashikvarma11, sorry I haven't gotten a chance to review the PR yet. For login checks, you can use the access_token cookie to check if the user is currently logged in. If not, you can handle it in a similarly to saving a playlist when a user is not logged in. Or, if you prefer, you could just hide the icons for liking the songs when a user isn't logged in.