fix: show author description on magazine article page

Add description field to ARTICLE_BY_SLUG_QUERY and render it in the
author bio card below the name.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/frontend/src/lib/services.ts

@@ -296,6 +296,7 @@ const ARTICLE_BY_SLUG_QUERY = gql`
         artist_name
         slug
         avatar
+        description
       }
     }
   }

packages/frontend/src/routes/magazine/[slug]/+page.svelte

@@ -151,10 +151,13 @@
                   class="w-16 h-16 rounded-full object-cover ring-2 ring-primary/20"
                 />
                 <div class="flex-1">
-                  <h3 class="font-semibold text-lg mb-2">About {author.artist_name}</h3>
+                  <h3 class="font-semibold text-lg mb-1">About {author.artist_name}</h3>
+                  {#if author.description}
+                    <p class="text-sm text-muted-foreground mb-3 leading-relaxed">{author.description}</p>
+                  {/if}
                   {#if author.slug}
                     <a href="/models/{author.slug}" class="text-sm text-primary hover:underline">
-                      View profile
+                      View profile →
                     </a>
                   {/if}
                 </div>