fix(wasm): request permission for media autoplay if needed

index.html

@@ -57,10 +57,12 @@ a, a:visited {
 import init from './target/lux-synthese.js'
 init()
 		</script>
+		<!-- workaround to be sure the browser will request permission to autoplay audio -->
+		<audio autoplay src="assets/silence.ogg"></audio>
 		<div id="readme">
 			<h1>Lux synthesĕ</h1>
 			<p>
-				<strong>Note</strong>: audio does not work in the WASM build.
+				<strong>If audio does not work, please allow media autoplay in browser, then refresh this page.</strong>
 			</p>
 			<h2>Controls</h2>
 			<ul>