[Playlist Tags] Add ability to chain operations for filtering

[ianrispin]

📝 Provide a description of the new feature

There are two parts to this request:

1. Add a NOT operator, to show all playlists that do not contain a certain tag
2. Add the ability to chain together groups of filtering commands like a boolean expression

➕ Additional Information

For example, if I wanted to listen to either folk playlists that are happy, or jazz playlists that are calm, the search would look something like:
(folk AND happy) OR (jazz AND calm)

If I then wanted to filter out "exciting" playlists from those results, it would be:
((folk AND happy) OR (jazz AND calm)) AND (NOT exciting)

[Bergbok]

Regarding part 1:

There already is a NOT operator, it's ! - so:
indie ![year:2020] would match all playlists tagged indie, but not those tagged as [year:2020]

---

Regarding part 2:

Great suggestion. The current dropdown implementation is pretty restrictive.