Read item combinations, added lettucedispenser in layout

overcooked_simulator/layouts/basic.layout → overcooked_simulator/game_content/layouts/basic.layout

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overcooked_simulator/game_items.py

 from __future__ import annotations
 
+import yaml
+
+from overcooked_simulator import ROOT_DIR
+
+with open(ROOT_DIR / "game_content/item_combinations.yaml", "r") as file:
+    item_loopkup = yaml.safe_load(file)
+
 
 class Item:
     """Base class for game items which can be held by a player."""