Add new assets and implement minimap functionality

- Added new image assets for game over screens: `game_over_dead_bg.png`, `game_over_victory_bg.png`, and their respective Aseprite files.
- Introduced a new `Minimap` class to manage torch placement and rendering on the minimap.
- Implemented methods for adding and removing torches, updating the grid area, and drawing the minimap based on the current state of the game.
- Enhanced the minimap display with color coding for walls, empty spaces, and torches.

settings/scene.rb

@@ -10,6 +10,6 @@ class Settings < Scene
   end
 
   def button_down(id, _pos)
-    $bus.emit(:change_scene, Menu.new) if id == Gosu::KB_ESCAPE
+    $bus.emit(:change_scene, Menu) if id == Gosu::KB_ESCAPE
   end
 end