[TASK] Content fixes

Assets/DuckStickerManager.cs

@@ -37,11 +37,26 @@ public class DuckStickerManager : MonoBehaviour
 
     private void Awake()
     {
+        CheckDuckStickers();
         foreach (var sticker in duckStickers)
         {
             _collectedStickers.Add(sticker, PlayerPrefs.GetInt("sticker." + sticker.Id));
         }
     }
+    
+    private void CheckDuckStickers()
+    {
+        var duckIds = new HashSet<string>();
+        foreach (var duck in duckStickers)
+        {
+            if (duckIds.Contains(duck.Id))
+            {
+                Debug.LogError("Duplicate duck ID: '" + duck.Id + "' for duck '" + duck.name + "'");
+            }
+
+            duckIds.Add(duck.Id);
+        }
+    }
 
     public void OnStickerCollected(DuckStickerData sticker)
     {