Sound work

-Added ambient sound for each biome.
-Music now plays randomly on a regular basis, the music volume slider still works in the game settings.
-By standard, now the volume of the music is very small (if you don't like it, just turn it to zero).
-Improved the sound of the robot flying over water.
-Reduced the volume of the steps of the protagonist.
-Some visual effects have been applied to the player's drone.