add group priorities for ordering groups

MiraAPI.Example/Options/ExampleOptions2.cs

@@ -8,6 +8,8 @@ public class ExampleOptions2 : AbstractOptionGroup
 {
     public override string GroupName => "Example Options 2";
 
+    public override uint GroupPriority => 0; // This group will be displayed first. The default value is uint.MaxValue.
+
     public ModdedToggleOption ToggleOpt1 { get; } = new("Toggle Option 1", false);
 
     public ModdedToggleOption ToggleOpt2 { get; } = new("Toggle Option 2", false)