adding scalajs & laminar

https://www.scala-js.org/doc/tutorial/laminar.html

vite.config.js

@@ -0,0 +1,6 @@
+import { defineConfig } from "vite";
+import scalaJSPlugin from "@scala-js/vite-plugin-scalajs";
+
+export default defineConfig({
+  plugins: [scalaJSPlugin()],
+});