Hide nonsensical dropdowns for gender/shiny

Internal values that were loosely bundled. The Criteria tab in the encdb shouldn't show these.

PKHeX.Core/Game/Enums/Gender.cs

@@ -1,4 +1,6 @@
-namespace PKHeX.Core;
+using System.ComponentModel;
+
+namespace PKHeX.Core;
 
 /// <summary>
 /// Gender a <see cref="PKM"/> can have
@@ -9,6 +11,6 @@ public enum Gender : byte
     Male = 0,
     Female = 1,
 
-    Genderless = 2,
+    [Browsable(false)] Genderless = 2,
     Random = Genderless,
 }

PKHeX.Core/Legality/Encounters/Templates/Enums/Shiny.cs

@@ -1,3 +1,5 @@
+using System.ComponentModel;
+
 namespace PKHeX.Core;
 
 /// <summary>
@@ -21,7 +23,7 @@ public enum Shiny : byte
     AlwaysSquare,
 
     /// <summary> PID is fixed to a specified value. </summary>
-    FixedValue,
+    [Browsable(false)] FixedValue,
 }
 
 /// <summary>