update example app

plugins/websocket/examples/svelte-app/src/app.d.ts

@@ -0,0 +1,9 @@
+// See https://kit.svelte.dev/docs/types#app
+// for information about these interfaces
+// and what to do when importing types
+declare namespace App {
+	// interface Error {}
+	// interface Locals {}
+	// interface PageData {}
+	// interface Platform {}
+}