Feat: Change current track's favorited state

[ducktordanny]

With the included changes we'll be able to mark a track as favorited or undo this via the following examples:

• Favorite: require('apple-music').set_current_track_favorited(true)
• Undo favorite: require('apple-music').set_current_track_favorited(false)

This command will also handle if the OS version is below 14 (Sonoma) where the favorited property was called loved. This is done via the osascript that @p5quared provided in the related issue's comment.

If the command succeeds it will prompt the change and the name plus the author of the track it was applied for.

With these changes, we're now also able to get the current track with require('apple-music').get_current_track() and it will return the name and author of the track in the following format <name> - <author>.

[p5quared]

I love this feature!

I left some notes. Here's what I'd like to see to merge:

1. get_current_track should just return the name, and leave it to users to decide what they want.
2. Split up set_current_track_favorited to favorite_current_track and unfavorite_current_track.

Optional:
What do you think about naming the split functions just favorite() and unfavorite()?
I don't think you can favorite anything besides tracks, and I doubt anyone will be trying to favorite/unfavorite anything besides the currently playing track.
In the future we could add favorite_track_by_name(name) or something if it is desired.

I left some other small suggestions like get_current_artist, I actually think I'd prefer those in separate PRs.
I'm active pretty much every day and am a fan of many tiny easy PRs over smushing everything together.

[ducktordanny]

As I've just checked you can also favorite playlists and albums as well. But I tried this in the app (iPhone) and it seems those don't show up in the built-in favorite songs playlist (I assume it only fetches the favorite tracks in the background), which is weird because then we can't see the favorited albums and playlists in a summary (at least in the app). Anyway, I think this should be included in another PR later on.

[p5quared]

As I've just checked you can also favorite playlists and albums as well.

Ha well I stand corrected on this part! I still think we start with assuming just songs and then we can add albums or playlists later.

[p5quared]

@ducktordanny When you're all set just re-request review from me.

[p5quared]

Looks great! ❤️

You are welcome to merge as is and I can do the minor refactor (moving the get_current_trackname() outside of M) if you want. Otherwise, if you do that refactor I'll also approve.

I also reworded some comments. Feel free to disagree if you feel strongly about them.

[ducktordanny]

Thanks, I made the suggested changes I think those make it better. 👌

[p5quared]

Awesome!

I'm merging this as is. I haven't really tested it much so I'll do that tonight and will put it in the next release probably with something for #17 as well.