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/Engines/ConPVP/Games/CTF.cs

@@ -29,7 +29,6 @@ namespace Server.Engines.ConPVP
         {
             if (m_TeamInfo?.Game != null)
             {
-                from.CloseGump<CTFBoardGump>();
                 from.SendGump(new CTFBoardGump(from, m_TeamInfo.Game));
             }
         }
@@ -56,6 +55,8 @@ namespace Server.Engines.ConPVP
 
         private CTFGame m_Game;
 
+        public override bool Singleton => true;
+
         public CTFBoardGump(Mobile mob, CTFGame game, CTFTeamInfo section = null)
             : base(60, 60)
         {
@@ -1059,7 +1060,6 @@ namespace Server.Engines.ConPVP
                 }
             }
 
-            mob.CloseGump<CTFBoardGump>();
             mob.SendGump(new CTFBoardGump(mob, this));
 
             m_Context.Requip(mob, corpse);
@@ -1258,7 +1258,6 @@ namespace Server.Engines.ConPVP
 
                     if (dp?.Mobile != null)
                     {
-                        dp.Mobile.CloseGump<CTFBoardGump>();
                         dp.Mobile.SendGump(new CTFBoardGump(dp.Mobile, this));
                     }
                 }