change: svelte5 対応

src/routes/code/[slug]/+layout.svelte

@@ -1,4 +1,6 @@
 <script>
+    let { children } = $props();
+
     import './app.css'
 
     function toggleFullScreen() {
@@ -25,7 +27,7 @@
         <button style="background-color: rgb(40 200 64)"  aria-label="fullscreen" onclick={toggleFullScreen}></button>
     </div>
     <div class="code">
-        <slot />
+        {@render children()}
     </div>
 </div>