start updating template for v3

src/routes/_error.html

@@ -1,14 +1,9 @@
-<svelte:head>
-	<title>{status}</title>
-</svelte:head>
+<script>
+	export let status;
+	export let error;
 
-<h1>{status}</h1>
-
-<p>{error.message}</p>
-
-{#if dev && error.stack}
-	<pre>{error.stack}</pre>
-{/if}
+	const dev = process.env.NODE_ENV === 'development';
+</script>
 
 <style>
 	h1, p {
@@ -32,10 +27,14 @@
 	}
 </style>
 
-<script>
-	export default {
-		helpers: {
-			dev: process.env.NODE_ENV === 'development'
-		}
-	};
-</script>
+<svelte:head>
+	<title>{status}</title>
+</svelte:head>
+
+<h1>{status}</h1>
+
+<p>{error.message}</p>
+
+{#if dev && error.stack}
+	<pre>{error.stack}</pre>
+{/if}