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

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

Content.Server/Store/StoreRefundComponent.cs

@@ -0,0 +1,13 @@
+using Content.Server.Store.Systems;
+
+namespace Content.Server.Store.Components;
+
+/// <summary>
+///     Keeps track of entities bought from stores for refunds, especially useful if entities get deleted before they can be refunded.
+/// </summary>
+[RegisterComponent, Access(typeof(StoreSystem))]
+public sealed partial class StoreRefundComponent : Component
+{
+    [ViewVariables, DataField]
+    public EntityUid? StoreEntity;
+}