Refactor input handling: replace hardcoded key inputs with configurable key bindings for character movement, inventory navigation, and actions; enhance settings scene with key rebind functionality and add credits scene.

game/weapons/handler.rb

@@ -27,7 +27,7 @@ class WeaponHandler
 
     weapon = @weapons[selected_item]
     if $bus.get(:count, selected_item) > 0
-      if id == Gosu::KB_SPACE
+      if id == $bus.get(:settings, :attack)
         player_x, player_y = $bus.get(:player_position)
         cam_x, cam_y = $bus.get(:camera_pos) || [0, 0]
         mouse_x, mouse_y = $bus.get(:mouse_pos) || [0, 0]