feat: Moves gumps out of the core (#1916)

> [!Important]
> **Developer Note**
> This code change will **completely move gumps out of the core**


### Summary

- Adds `GetGumps()` convenience which exposes methods to Find/Close/Send multiple gumps. This helper is a performance improvement by eliminating the Dictionary<Player, List> lookup for gumps.

Projects/UOContent/Gumps/PetResurrectGump.cs

@@ -8,10 +8,10 @@ public class PetResurrectGump : StaticGump<PetResurrectGump>
     private readonly double _hitsScalar;
     private readonly BaseCreature _pet;
 
+    public override bool Singleton => true;
+
     public PetResurrectGump(Mobile from, BaseCreature pet, double hitsScalar = 0.0) : base(50, 50)
     {
-        from.CloseGump<PetResurrectGump>();
-
         _pet = pet;
         _hitsScalar = hitsScalar;
     }