use channels for comms (#9)

this  refactors the app setup and messaging modules

static/index.html

@@ -14,8 +14,8 @@
       height: 100%;
     }
     canvas {
-      width: 90%;
-      height: 300px;
+      width: 100%;
+      height: 100vh;
       background-color: yellowgreen;
     }
   </style>
@@ -26,7 +26,6 @@
       <ul>
       </ul>
     </nav>
-    <h1 class="title">Enjoy WebGPU + WASM + Webpack with 🍰☕</h1>
   </header>
   <main>
     <section>

static/index.js

@@ -1,10 +1,13 @@
-import wbg_init, { main, App } from "../pkg/wasm-index.js";
+import wbg_init, { main } from "../pkg/wasm-index.js";
 
 const start = async () => {
   await wbg_init();
-
   main();
-  const app = new App();
 };
 
-start();
+// Wait for DOM to be ready before starting
+if (document.readyState === 'loading') {
+  document.addEventListener('DOMContentLoaded', start);
+} else {
+  start();
+}