Add explosion stage 1 PNG assets for all directions

- Added BMP_1_EXPLOSION_DOWN.png to original and preview directories.
- Added BMP_1_EXPLOSION_LEFT.png to original and preview directories.
- Added BMP_1_EXPLOSION_RIGHT.png to original and preview directories.
- Added BMP_1_EXPLOSION_UP.png to original and preview directories.

These assets are part of the explosion animation for the game, enhancing visual effects during gameplay.

rats.py

@@ -281,7 +281,6 @@ class MiceMaze(
         self.render_engine.delete_tag("unit")
         self.render_engine.delete_tag("effect")
         self.render_engine.delete_tag("cave")
-        self.render_engine.draw_pointer(self.pointer[0] * self.cell_size, self.pointer[1] * self.cell_size)
         
         # Clear collision system for new frame
         self.collision_system.clear()
@@ -333,13 +332,14 @@ class MiceMaze(
             self.unit_positions.setdefault(unit.position, []).append(unit)
             self.unit_positions_before.setdefault(unit.position_before, []).append(unit)
         
+        self.draw_cave_foreground()
+        self.render_engine.draw_pointer(self.pointer[0] * self.cell_size, self.pointer[1] * self.cell_size)
         
         # Fourth pass: check collisions and draw
         for unit in self.units.copy().values():
             unit.collisions()
             unit.draw()
 
-        self.draw_cave_foreground()
         
         self.render_engine.update_status(f"Mice: {self.count_rats()} - Points: {self.points}")
         self.refill_ammo()