Separate part management from the rest of body manager component (#2017)

* Separate part management from the rest of body manager component

* Component reference

* Move more methods over

* Fix docs and move over BodyPreset

* Fix up body preset

* Create initialize method and remove constructor for BodyPreset

* Do the same for BodyTemplate and add Initialized properties

* Fix BodyTemplate HashCode test

* BodyTemplate test PLS

Content.Server/Body/Network/BodyNetwork.cs

@@ -31,9 +31,16 @@ namespace Content.Server.Body.Network
         public virtual void OnRemove() { }
 
         /// <summary>
-        ///     Called every update by <see cref="BodyManagerComponent.Update"/>.
+        ///     Called every update by
+        ///     <see cref="BodyManagerComponent.PreMetabolism"/>.
         /// </summary>
-        public virtual void Update(float frameTime) { }
+        public virtual void PreMetabolism(float frameTime) { }
+
+        /// <summary>
+        ///     Called every update by
+        ///     <see cref="BodyManagerComponent.PostMetabolism"/>.
+        /// </summary>
+        public virtual void PostMetabolism(float frameTime) { }
     }
 
     public static class BodyNetworkExtensions