feat(db): StoryDeckEntry presentation table + StoryDeckKind enum

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

SVSim.Database/Models/StoryDeckEntry.cs

@@ -0,0 +1,28 @@
+using SVSim.Database.Common;
+using SVSim.Database.Enums;
+
+namespace SVSim.Database.Models;
+
+/// <summary>
+/// Presentation metadata for a story-mode prebuilt/trial deck, as surfaced under
+/// main_story/get_deck_list's build_deck_list / trial_deck_list. PK (DeckNo) equals the deck's
+/// wire deck_no, which also equals BuildDeckProductEntry.Id — the 40-card list is read from that
+/// product (single source of truth), NOT stored here. Sourced from
+/// data_dumps/traffic_prod_trial_decks.ndjson via seeds/story-decks.json.
+/// </summary>
+public class StoryDeckEntry : BaseEntity<int>
+{
+    public int DeckNo { get => Id; set => Id = value; }   // == BuildDeckProductEntry.Id
+
+    public StoryDeckKind Kind { get; set; }
+    public int ClassId { get; set; }
+    public string DeckName { get; set; } = string.Empty;
+    public int SleeveId { get; set; }
+    public int LeaderSkinId { get; set; }
+    public int IsRecommend { get; set; }
+    public int OrderNum { get; set; }
+    public int EntryNo { get; set; }
+
+    /// <summary>Trial decks carry a deck_format on the wire; build decks do not (null).</summary>
+    public int? DeckFormat { get; set; }
+}