update svelte config

This restores the creation of HTML files after this was broken by a recent change to sveltekit: sveltejs/kit#4192

Author: jamesscottbrown

packages/vistorian-web-sveltekit/svelte.config.js

@@ -14,7 +14,11 @@ const config = {
 			pages: 'build',
 			assets: 'build',
 			fallback: null
-		})
+		}),
+		
+		prerender: {
+			default: true
+		}
 	}
 };