feat: Implement quest reward system with item selection and storage; update related services and database schema

DorkNet.Server/Data/Entities/GameRewardSelectionEntity.cs

@@ -12,4 +12,15 @@ public class GameRewardSelectionEntity
     public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
     public DateTime? SelectedAt { get; set; }
     public int? SelectedGiftDropId { get; set; }
+
+    /// <summary>The three store-item ids offered as the choose-1-of-3
+    /// reward. Persisted so re-fetching the pending reward is stable and
+    /// <c>/select</c> can grant exactly what was shown. 0 = empty slot.</summary>
+    public long Offer1ItemId { get; set; }
+    public long Offer2ItemId { get; set; }
+    public long Offer3ItemId { get; set; }
+
+    /// <summary>Set once the chosen item has been granted to inventory, so
+    /// a replayed <c>/select</c> can't grant twice.</summary>
+    public long GrantedItemId { get; set; }
 }

DorkNet.Server/Data/quest_rewards.json

@@ -0,0 +1,4 @@
+{
+  "_comment": "Per-quest reward chest contents. Keyed by the RRO room id the player is in when they open the end-of-quest gift box (the gifts/generate request carries no quest id, so the server keys off the player's current room via presence). Each entry lists the store-item slugs that quest can award; the server picks one at random from the list. Slugs use the same scheme as the store: wardrobe-{guid} for outfits, consumable-{name} for consumables, equipment-{prefab}:{guid} for equipment. Populate `rooms` with real roomId -> item-slug lists.",
+  "rooms": {}
+}