fix: small playground bug

sites/svelte-5-preview/src/lib/Output/Viewer.svelte

@@ -246,6 +246,8 @@
 	function clear_logs() {
 		current_log_group = logs = [];
 	}
+
+	$: src = BROWSER ? srcdoc : '';
 </script>
 
 <div class="iframe-container">
@@ -266,7 +268,7 @@
 					relaxed ? 'allow-same-origin' : ''
 				].join(' ')}
 				class={error || pending || pending_imports ? 'greyed-out' : ''}
-				srcdoc={BROWSER ? srcdoc : ''}
+				srcdoc={src}
 			></iframe>
 
 			{#if $bundle?.error}