dto(card): CardCreate request and response

SVSim.EmulatedEntrypoint/Models/Dtos/Requests/Card/CardCreateRequest.cs

@@ -0,0 +1,19 @@
+using MessagePack;
+using System.Text.Json.Serialization;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Requests.Card;
+
+/// <summary>
+/// POST /card/create. The single payload field is a JSON-encoded STRING (double-encoded —
+/// see docs/api-spec/endpoints/post-login/card-create.md). Inner object maps
+/// cardId → "&lt;num_to_create&gt;,&lt;client_possession_snapshot&gt;". Both inner values
+/// are strings. Same wire format as /card/destruct; CardController parses both with the
+/// shared TryParseCardCountDict helper.
+/// </summary>
+[MessagePackObject]
+public class CardCreateRequest : BaseRequest
+{
+    [JsonPropertyName("card_id_number_array")]
+    [Key("card_id_number_array")]
+    public string CardIdNumberArray { get; set; } = string.Empty;
+}