chore(frontend/MkMediaVideo): loop and autoplay silent videos (#12392)

packages/frontend/src/scripts/media-has-audio.ts

@@ -0,0 +1,9 @@
+export default async function hasAudio(media: HTMLMediaElement) {
+	const cloned = media.cloneNode() as HTMLMediaElement;
+	cloned.muted = (cloned as typeof cloned & Partial<HTMLVideoElement>).playsInline = true;
+	cloned.play();
+	await new Promise((resolve) => cloned.addEventListener('playing', resolve));
+	const result = !!(cloned as any).audioTracks?.length || (cloned as any).mozHasAudio || !!(cloned as any).webkitAudioDecodedByteCount;
+	cloned.remove();
+	return result;
+}