Add support for left click actions

src/Dodge/Creature/Action/UseItem.hs

@@ -5,7 +5,7 @@ import Dodge.Inventory
 
 import qualified Data.IntMap as IM
 import Control.Lens
---import Data.Maybe (maybe)
+import Data.Maybe
 
 useItem :: Int -> World -> World
 useItem n w = itemEffect c it w
@@ -35,3 +35,15 @@ itemEffect cr Consumable{_cnEffect=eff } w = maybe w (rmSelectedInvItem (_crID c
 itemEffect cr Weapon{_itUse=eff} w = eff cr w
 itemEffect cr Throwable{_itUse = eff} w = eff cr w
 itemEffect _ _ w = w
+
+useLeftItem
+    :: Int
+    -> World
+    -> World
+useLeftItem cid w = case luse of
+    Nothing -> w
+    Just (invid, f) -> f cr invid w
+  where
+    cr = _creatures w IM.! cid
+    luses = IM.mapMaybe (^? itLeftClickUse . _Just) (_crInv cr)
+    luse = listToMaybe $ IM.toList luses