Update minigame switcher to only unlock when all puzzles completed

Assets/Scripts/Core/SaveLoad/SaveLoadData.cs

@@ -9,6 +9,9 @@ namespace Core.SaveLoad
         
         // Snapshot of the player's card collection (MVP)
         public CardCollectionState cardCollection;
+
+        // List of unlocked minigames by name
+        public List<string> unlockedMinigames = new List<string>();
     }
 
     // Minimal DTOs for card persistence