Additional card content

SVSim.EmulatedEntrypoint/Services/ICardAcquisitionService.cs

@@ -0,0 +1,18 @@
+namespace SVSim.EmulatedEntrypoint.Services;
+
+public interface ICardAcquisitionService
+{
+    /// <summary>
+    /// Grant cards + associated cosmetics in one transaction.
+    ///
+    /// • <paramref name="newCardIds"/> non-null  → increments OwnedCardEntry for each via
+    ///   the existing IPackRepository.GrantCardsToViewer primitive, then grants any
+    ///   cosmetics associated with those cards that the viewer doesn't yet own.
+    /// • <paramref name="newCardIds"/> null      → backfill mode: skips card mutation,
+    ///   scans viewer.Cards, grants missing cosmetics.
+    ///
+    /// Returns wire-shape RewardList in both modes. Backfill callers typically discard.
+    /// All ownership writes happen in a single SaveChangesAsync.
+    /// </summary>
+    Task<CardGrantResult> GrantAsync(long viewerId, IEnumerable<long>? newCardIds = null);
+}