Adds a refund button & action upgrades for stores (#24518)

* adds refunds to stores

* Adds method to check for starting map

* comments, datafields, some requested changes

* turns event into ref event

* Adds datafields

* Switches to entity terminating event

* Changes store entity to be nullable and checks if store is terminating to remove reference.

* Tryadd instead of containskey

* Adds a refund disable method, disables refund on bought ent container changes if not an action

* Removes datafield specification

* Readds missing using statement

* Removes unused using statements

* What the heck is listing data

---------

Co-authored-by: metalgearsloth <comedian_vs_clown@hotmail.com>

Content.Server/Store/Systems/StoreSystem.cs

@@ -36,12 +36,14 @@ public sealed partial class StoreSystem : EntitySystem
 
         InitializeUi();
         InitializeCommand();
+        InitializeRefund();
     }
 
     private void OnMapInit(EntityUid uid, StoreComponent component, MapInitEvent args)
     {
         RefreshAllListings(component);
         InitializeFromPreset(component.Preset, uid, component);
+        component.StartingMap = Transform(uid).MapUid;
     }
 
     private void OnStartup(EntityUid uid, StoreComponent component, ComponentStartup args)