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/Factions/Core/Faction.cs

@@ -5,6 +5,7 @@ using Server.Commands.Generic;
 using Server.Engines.ConPVP;
 using Server.Ethics;
 using Server.Guilds;
+using Server.Gumps;
 using Server.Items;
 using Server.Mobiles;
 using Server.Prompts;