fix: Add margin-right to player download button for better spacing

Player.tsx: Download button now has mr-2 (margin-right: 0.5rem) to
create more breathing room between the download icon and the album art
thumbnail.

frontend/src/components/Player.tsx

@@ -256,7 +256,7 @@ export default function Player({ clip, isPlaying, onTogglePlay, onStop, onClose
           <div className="hidden sm:flex items-center gap-2.5 min-w-0 max-w-[220px] shrink-0">
             <button
               onClick={() => window.open(`/api/clips/${clip.id}/download`, '_blank')}
-              className="text-lyria-muted/60 hover:text-lyria-accent transition-colors shrink-0"
+              className="text-lyria-muted/60 hover:text-lyria-accent transition-colors shrink-0 mr-2"
               title="Download MP3"
             >
               <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">