fix(queue): improve Up Next counter with total, remaining, and infinite modes

- Show format: (20 of 139, 135 left) for normal playback
- Show format: (20 of ∞) for infinite play or radio mode
- Remove Load More from Queue section (not needed)
- Add Load More to History section for tracks > 20
- Add isRadioMode prop to detect radio context
- Pass both queueTotalTracks and queueRemainingTracks

src/routes/+page.svelte

@@ -2532,8 +2532,10 @@
       onClose={closeQueue}
       currentTrack={currentQueueTrack ?? undefined}
       upcomingTracks={queue}
-      queueTotalTracks={queueRemainingTracks}
+      {queueTotalTracks}
+      {queueRemainingTracks}
       {historyTracks}
+      isRadioMode={getCurrentContext()?.type === 'radio'}
       onPlayTrack={handleQueueTrackPlay}
       onPlayHistoryTrack={handlePlayHistoryTrack}
       onClearQueue={handleClearQueue}