Allow playSound volume

Engine/src/shared/audio.ts

@@ -88,16 +88,21 @@ export function playSong(name: string) {
   }
 }
 
-export function playSound(name: string): HTMLAudioElement {
+export function playSound(name: string, volume: number): HTMLAudioElement {
   let s = new Audio()
   if (!enabled) return s
 
   s.src = audio[name]
+  s.volume = volume
   s.autoplay = true
   s.preload = ''
-  ;(async () => {
+  let promise = s.play()
-    await s.play()
+  if (promise !== undefined) {
-  })()
+    promise.then(() => {
+      // ok
+    }).catch((error: any) => {
+    })
+  }
 
   return s
 }