Refactor more stuff (Audio mostly)

Zennysoft.Game.Abstractions/Audio/IDimmableAudioStreamPlayer.cs

@@ -0,0 +1,13 @@
+namespace Zennysoft.Game.Abstractions;
+
+public interface IDimmableAudioStreamPlayer
+{
+  /// <summary>Fade this dimmable audio stream track in.</summary>
+  public void FadeIn();
+  /// <summary>Fade this dimmable audio stream track out.</summary>
+  public void FadeOut();
+
+  public void Play(float fromPosition = 0);
+
+  public void Stop();
+}