update to svelte 5

frontend/src/App.svelte

@@ -5,7 +5,11 @@
   import Home from "./routes/Home.svelte";
   import "./app.css";
   import Tournament from "./routes/Tournament.svelte";
-  export let url = "";
+  interface Props {
+    url?: string;
+  }
+
+  let { url = $bindable("") }: Props = $props();
 </script>
 
 <main class="flex-col h-screen items-center bg-gray-50 dark:bg-gray-800">
@@ -18,8 +22,10 @@
   <Router bind:url>
     <div>
       <Route path="/"><Home /></Route>
-      <Route path="/tournament/:id" let:params
-        ><Tournament id={params.id} /></Route
+      <Route path="/tournament/:id" 
+        >{#snippet children({ params })}
+                <Tournament id={params.id} />              {/snippet}
+            </Route
       >
     </div>
   </Router>