Replace the bespoke SceneArtistCard in ArtistsByLocationView with the
app-wide ArtistGridCard (follow / play / pin / context menu, homologated
with the other artist carousels). The scene model rides the shared
SlimItem (LocationArtistItem deleted): genres land in the subtitle — the
card's second row under the name, as requested. Follow and pin states
seed from the disk-backed caches at map time; mark_artist_followed now
walks the scene model too, so toggles from any surface flip the chips
live. ArtworkTarget::LocationArtist writeback updated for the SlimItem
artwork field; media-action routed through AppShell. Cards at 200x246
(AlbumCard parity).
km