fix: the cost of entering water in a-star alg is now 1000.

src/tractor.py

@@ -109,6 +109,8 @@ class Tractor(pygame.sprite.Sprite):
         match (self.field.tiles.sprites()[y * 16 + x].type):
             case ('grass'):
                 cost = 1
+            case ('water'):
+                cost = 1000
             case _:
                 cost = 100
         return cost