[Player][Interaction][Assets] Add placeholder assets for some more sprites. Move all to External/Placeholder. Add list of assets with attributions. Pulver combines items now

Assets/Scripts/CombineWithBehavior.cs

@@ -0,0 +1,40 @@
+using UnityEngine;
+
+[RequireComponent(typeof(Pickup))]
+public class CombineWithBehavior : InteractionRequirementBase
+{
+    public override bool TryInteract(FollowerController follower)
+    {
+        var heldItem = follower.currentlyHeldItem;
+        var pickup = GetComponent<Pickup>();
+        if (heldItem == null)
+        {
+            DebugUIMessage.Show("You need an item to combine.");
+            OnFailure?.Invoke();
+            return false;
+        }
+        if (pickup == null || pickup.itemData == null)
+        {
+            DebugUIMessage.Show("Target item is missing or invalid.");
+            OnFailure?.Invoke();
+            return false;
+        }
+        var rule = GameManager.Instance.GetCombinationRule(heldItem, pickup.itemData);
+        if (rule != null && rule.result != null)
+        {
+            // Remove both items and add result to follower's inventory
+            follower.SetHeldItem(rule.result);
+            follower.justCombined = true;
+            OnSuccess?.Invoke();
+            return true;
+        }
+        else
+        {
+            string heldName = heldItem.itemName ?? "an item";
+            string targetName = pickup.itemData.itemName ?? "target item";
+            DebugUIMessage.Show($"Cannot combine {heldName} with {targetName}.");
+            OnFailure?.Invoke();
+            return false;
+        }
+    }
+}