Consolidate Fluxon usage via CoreComponents

With the exclusion of 'button' which is already in use an may need a
refactor

lib/music_library_web/live/artist_live/show.html.heex

@@ -9,7 +9,7 @@
       <.async_result :let={lastfm_artist_info} assign={@lastfm_artist_info}>
         <:loading>
           <span class="sr-only">{gettext("Loading play count")}</span>
-          <Fluxon.Components.Loading.loading />
+          <.loading />
         </:loading>
         <:failed :let={_failure}>
           <div class="mt-4 text-sm leading-5 text-zinc-500 dark:text-zinc-400">