Adds latest episode api endpoint and some other minor modifications.

site/app/Models/Podcast.php

@@ -33,4 +33,27 @@ class Podcast extends Model
         return $this->hasManyThrough(Artist::class, Episode::class);
     }
 
+    public function latestEpisode()
+    {
+        return $this->hasOne(Episode::class)
+                    ->where('published', true)
+                    ->orderBy('episode_number', 'desc');
+    }
+
+    public function latestArtwork()
+    {
+        // this follows the hasOneThrough from Episode → Artwork
+        return $this->hasOneThrough(
+            Artwork::class,    // final model
+            Episode::class,    // intermediate
+            'podcast_id',      // FK on episodes
+            'id',              // PK on artworks
+            'id',              // PK on podcasts
+            'artwork_id'       // FK on episodes → artworks
+        )
+        ->where('episodes.published', true)
+        ->orderBy('episodes.episode_number', 'desc');
+    }
+
+
 }