feat(store): populate shops via GetStoreItems

GetStoreItems was a stub returning an empty object, so every shop
(Korolev / ICA / Osiris / QuickShop vendors) showed up empty. Build the
store on the fly from the Blueprints title data: for the requested
StoreId, list every item that declares an ItemShopsCraftingData entry
for that store, converting its currency recipe ingredients into
VirtualCurrencyPrices (SoftCurrency->SC, Aurum->AU, InsuranceCurrency->IN).
Item-ingredient (crafting) entries are left to the crafting UI.

Adds the StoreId/CatalogVersion fields to the request and the
FGetStoreItemsResult / FStoreItem PlayFab response models.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/Prospect.Server.Api/Models/Client/Data/FStoreItem.cs

@@ -0,0 +1,39 @@
+using System.Text.Json.Serialization;
+
+namespace Prospect.Server.Api.Models.Client.Data;
+
+// PlayFab StoreItem: a single catalog item offered for sale in a store, with its prices.
+public class FStoreItem
+{
+    /// <summary>
+    ///     [optional] Store specific custom data. The data only exists as part of this store; it is not transferred to item instances.
+    /// </summary>
+    [JsonPropertyName("CustomData")]
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingDefault)]
+    public object? CustomData { get; set; }
+
+    /// <summary>
+    ///     [optional] Intended display position for this item. Note that 0 is the first position and -1 is the last position.
+    /// </summary>
+    [JsonPropertyName("DisplayPosition")]
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingDefault)]
+    public uint? DisplayPosition { get; set; }
+
+    /// <summary>
+    ///     Unique identifier of the item as it exists in the catalog - note that this must exactly match the ItemId from the catalog.
+    /// </summary>
+    [JsonPropertyName("ItemId")]
+    public string ItemId { get; set; } = "";
+
+    /// <summary>
+    ///     [optional] Override prices for this item for specific currencies.
+    /// </summary>
+    [JsonPropertyName("RealCurrencyPrices")]
+    public Dictionary<string, uint> RealCurrencyPrices { get; set; } = new();
+
+    /// <summary>
+    ///     [optional] Override prices for this item in virtual currencies and "RM" (the base Real Money purchase price, in USD pennies).
+    /// </summary>
+    [JsonPropertyName("VirtualCurrencyPrices")]
+    public Dictionary<string, uint> VirtualCurrencyPrices { get; set; } = new();
+}

src/Prospect.Server.Api/Models/Client/FGetStoreItems.cs

@@ -1,8 +1,19 @@
-using System.Text.Json.Serialization;
+using System.Text.Json.Serialization;
 using Prospect.Server.Api.Models.Client.Data;
 
 namespace Prospect.Server.Api.Models.Client;
 
 public class FGetStoreItems
 {
-}
+    /// <summary>
+    ///     [optional] Catalog version to store items from. Use default catalog version if null.
+    /// </summary>
+    [JsonPropertyName("CatalogVersion")]
+    public string? CatalogVersion { get; set; }
+
+    /// <summary>
+    ///     Unique identifier for the store which is being requested.
+    /// </summary>
+    [JsonPropertyName("StoreId")]
+    public string? StoreId { get; set; }
+}

src/Prospect.Server.Api/Models/Client/FGetStoreItemsResult.cs

@@ -0,0 +1,25 @@
+using System.Text.Json.Serialization;
+using Prospect.Server.Api.Models.Client.Data;
+
+namespace Prospect.Server.Api.Models.Client;
+
+public class FGetStoreItemsResult
+{
+    /// <summary>
+    ///     [optional] The base catalog that this store is a part of.
+    /// </summary>
+    [JsonPropertyName("CatalogVersion")]
+    public string? CatalogVersion { get; set; }
+
+    /// <summary>
+    ///     [optional] Array of items which can be purchased from this store.
+    /// </summary>
+    [JsonPropertyName("Store")]
+    public List<FStoreItem> Store { get; set; } = new();
+
+    /// <summary>
+    ///     [optional] The ID of this store.
+    /// </summary>
+    [JsonPropertyName("StoreId")]
+    public string? StoreId { get; set; }
+}