Raw play count conflates two different kinds of favourite: an artist you binged hard for a week, and one you've quietly kept coming back to for months. Tracks each artist's distinct ISO weeks played in and surfaces a "Long-Time Favourites" list ranked by that instead — ported from lastfm-stats-web's "weeks per artist" list. Requires >= 2 weeks active to appear, so one-off binges don't show up as false "long-time favourites" with a weeksActive of 1.