fix(core): Removes some uses of Linq (#421)

- [X] Removes some uses of linq
- [X] Creates struct based enumerator for Skills
- [X] Creates a struct based enumerator for TypeCache
- [X] Changes HarvestDefinition to an init array instead of List
- [X] Changes HeritageTokenGump Response from List to Array

Projects/UOContent/Engines/Craft/DefAlchemy.cs

@@ -17,7 +17,7 @@ namespace Server.Engines.Craft
 
         public override int GumpTitleNumber => 1044001;
 
-        public static CraftSystem CraftSystem => m_CraftSystem ?? (m_CraftSystem = new DefAlchemy());
+        public static CraftSystem CraftSystem => m_CraftSystem ??= new DefAlchemy();
 
         public override double GetChanceAtMin(CraftItem item) => 0.0;