At this point its primary usage is the daily challenge event feed, but
the leaderboard will be using this too shortly.
Because the playlists results screen that exists in `master` is
hard-coupled to showing the *local user's* best result on a given
playlist by way of hard-coupling itself to the relevant API request,
allowing show of *arbitrary* score by ID requires a whole bunch of
subclassery as things stand. Oh well.
Class naming is... best effort, due to the above.
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