add csound minimal example

packages/csound/example/main.js

@@ -0,0 +1,27 @@
+import { Csound } from '@csound/browser';
+import './style.css';
+import csd from './tutorial1.csd?raw';
+
+document.querySelector('#app').innerHTML = `
+  <div>
+    <button id="startButton">Start</button>
+  </div>
+`;
+
+let csound = null;
+const startCsound = async () => {
+  if (csound) {
+    return;
+  }
+  console.log('Starting Csound...');
+  csound = await Csound();
+  console.log(csound);
+  window.csound = csound;
+
+  await csound.compileCsdText(csd);
+  await csound.start();
+
+  document.querySelector('#startButton').remove();
+};
+
+document.querySelector('#startButton').addEventListener('click', startCsound);