use SvelteSet instead of Set for favoritedStreams

src/routes/streams/Sidebar.svelte

@@ -1,7 +1,7 @@
 <script lang="ts">
     import { untrack } from 'svelte';
     import { goto } from '$app/navigation';
-    import { currentStream, favoritedStreams } from '$lib/stores.js';
+    import { currentStream, favoritedStreams } from '$lib/stores.svelte.js';
     import { hashColor, shorthandCode, formatSecondsToHms, formatDate } from '$lib/utils.js';
     import TagSelect from './TagSelect.svelte';
 
@@ -40,10 +40,9 @@
     }
 
     function updateFavorites(stream) {
-        $favoritedStreams.has(stream['id'])
-            ? $favoritedStreams.delete(stream['id'])
-            : $favoritedStreams.add(stream['id']);
-        $favoritedStreams = $favoritedStreams; // for reactivity
+        favoritedStreams.has(stream['id'])
+            ? favoritedStreams.delete(stream['id'])
+            : favoritedStreams.add(stream['id']);
     }
 </script>
 
@@ -57,7 +56,7 @@
 
 <ul class="stream-list">
     {#each streams as stream}
-        {@const favorited = $favoritedStreams.has(stream['id'])}
+        {@const favorited = favoritedStreams.has(stream['id'])}
         {@const current = $currentStream['id'] === stream['id']}
         <li
             hidden={!displayedStreams.includes(stream) || (favoritesOnly && !favorited)}