fix(oembed.sql): return top artist image for oembed on genre pages

queries/views/feeds/oembed.sql

@@ -49,10 +49,15 @@ WITH oembed_data AS (
     CURRENT_TIMESTAMP AS content_date
   FROM optimized_genres g
   LEFT JOIN LATERAL (
-    SELECT ar.image
-    FROM optimized_artists ar
-    WHERE (ar.genre->>'id')::bigint = g.id
-    ORDER BY ar.total_plays DESC
+    SELECT
+      CASE
+        WHEN df.filename_disk IS NOT NULL AND df.filename_disk != '' THEN CONCAT('/', df.filename_disk)
+        ELSE (SELECT avatar FROM optimized_globals LIMIT 1)
+      END AS image
+    FROM artists a
+    LEFT JOIN directus_files df ON a.art = df.id
+    WHERE a.genres = g.id
+    ORDER BY a.total_plays DESC
     LIMIT 1
   ) top_artist ON true
   UNION ALL