feat: #26107 uplink discounts for traitors (no nukies for now) (#26297)

* feat: #26107 uplink discounts for traitors and nukies

* refactor: #26107 extracted discount label from price of StoreListingControl

* refactor: minor renaming

* refactor: parametrized adding discounts to uplink store

* fix: #26107 prevent exception on empty discountOptions

* feat: uplink now have 'Discounted' category which contains all discounted items on this session.

* after merge fixups

* rename discount categories according to common sense

* refactor: DiscountOptions is now optional (nullable) on ListingData

* add nullability check ignore for already checked listingData.DiscountOptions

* fix after merge store menu ui

* remove unused using

* final fix after merge conflicts

* [refactor]: #26107 fix variables naming in UplinkSystem

* fix: #26107 fix after merge

* refactor: #26107 now supports discountDownUntil on ListingItem, instead of % of discount

* feat: #26107 support multiple currency discount in store on side of discount message label

* refactor: #26107 extracted discounts initialization to separate system. StoreDiscountData are spread as array and not list now

* refactor: #26107 move more code from storesystem to StoreDiscountComponent

* refactor: #26107 separated StoreSystem and StoreDiscountSystem using events

* fix: #26107 placed not-nullable variable initialization in ListingData for tests

* refactor: #26107 minor renaming, xml-docs

* fix: #26107 changed most of discounts to be down to half price for balance purposes

* ids used in with discounts are now ProtoIds, dicountCategories are now prototypes, code with weights simplified

* decoupled storesystem and store discount system

* xml-docs

* refactor:  #26107 xml-doc for StoreDiscountSystem

* is now a thing (tmp)

* fix: compilation errors + StoreDiscountData.DiscountCategoryId

* refactor: rename ListingDataWithCostModifiers, fix all cost related code, enpittyfy performance, uglify uplink_catalog

* refactor: removed unused code, more StoreDiscountSystem docs, simplify code

* refactor: moved discount category logic to respective system, now creating ListingData c-tor clones all mutable fields as expected

* refactor: rename back (its not prototype)

* refactor: move ListingItemsInitializingEvent to file with handling logic

* refactor: comments for StoreBuyFinishedEvent handling, more logging

* refactor: moved StoreInitializedEvent, xml-doc

* refactor: simplify StoreDiscountSystem code  (reduce nesting) + xml-doc

* refactor: restore old listing data cost field name

* refactor: fix linter in uplink_catalog.yml

* refactor: xml-doc for ListingDataWithCostModifiers

* refactor: limit usage of ListingData in favour of ListingDataWithCostModifiers

* refactor: purged linq, removed custom datafield names, minor cleanup

* refactor: removed double-allocation on getting available listings

* refactor: StoreSystem.OnBuyRequest now uses component.FullListingsCatalog as reference point (as it was in original code)

* fix: minor discount categories on uplink items changes following design overview

* refactor: StoreBuyListingMessage now uses protoId and not whole object

* refactor: store refund and discount integration test, RefreshAllListings now translates previous cost modifiers to refreshed list, if state previous to refresh had any listing items

---------

Co-authored-by: pa.pecherskij <pa.pecherskij@interfax.ru>

Content.Shared/Store/Components/StoreComponent.cs

@@ -2,7 +2,6 @@ using Content.Shared.FixedPoint;
 using Robust.Shared.Audio;
 using Robust.Shared.GameStates;
 using Robust.Shared.Prototypes;
-using Robust.Shared.Serialization.TypeSerializers.Implementations.Custom.Prototype;
 
 namespace Content.Shared.Store.Components;
 
@@ -45,16 +44,16 @@ public sealed partial class StoreComponent : Component
     public EntityUid? AccountOwner = null;
 
     /// <summary>
-    /// All listings, including those that aren't available to the buyer
+    /// Cached list of listings items with modifiers.
     /// </summary>
     [DataField]
-    public HashSet<ListingData> Listings = new();
+    public HashSet<ListingDataWithCostModifiers> FullListingsCatalog = new();
 
     /// <summary>
     /// All available listings from the last time that it was checked.
     /// </summary>
     [ViewVariables]
-    public HashSet<ListingData> LastAvailableListings = new();
+    public HashSet<ListingDataWithCostModifiers> LastAvailableListings = new();
 
     /// <summary>
     ///     All current entities bought from this shop. Useful for keeping track of refunds and upgrades.