[web] optimize client requests

apps/web/src/api/library.ts

···
 import { client } from ".";
 
 export const getSongByUri = async (uri: string) => {
+  if (uri.includes("app.rocksky.scrobble")) {
+    return null;
+  }
+
   const response = await client.get("/xrpc/app.rocksky.song.getSong", {
     params: { uri },
   });

apps/web/src/pages/song/Song.tsx

···
 
   const loading =
     songResult.isLoading ||
+    scrobbleResult.isLoading ||
     artistTracksResult.isLoading ||
     artistAlbumResult.isLoading;