chore(*): remove duplicate cache rule + cleanup cache headers; cleanup + formatting

api/Classes/ArtistFetcher.php

@@ -8,12 +8,15 @@ class ArtistFetcher extends PageFetcher
   {
     $cacheKey = "artist_" . md5($url);
     $cached = $this->cacheGet($cacheKey);
+
     if ($cached) return $cached;
 
     $artist = $this->fetchSingleFromApi("optimized_artists", $url);
+
     if (!$artist) return null;
 
     $this->cacheSet($cacheKey, $artist);
+
     return $artist;
   }
 }