Add main theme music functionality; implement enable/disable scripts and audio resources

Scripts/DisableMainThemeMusic.cs

@@ -0,0 +1,12 @@
+using Godot;
+
+namespace ParasiticGod.Scripts;
+
+public partial class DisableMainThemeMusic : Node
+{
+    public override void _Ready()
+    {
+        var mainThemeMusic = GetNodeOrNull<AudioStreamPlayer>("/root/MainThemeMusic");
+        mainThemeMusic?.Stop();
+    }
+}