Enhanced snail entity with new features

Added a sprite to the Snail class and implemented animations for the snail's movements. The snail now has a body and shell texture, along with an eating shadow. Also, added logic to flip the sprite based on movement direction in the 'snail_eating' state. Furthermore, made CollisionShape2D invisible for better aesthetics.

entities/scripts/snail.gd

@@ -3,6 +3,7 @@ class_name Snail
 
 @onready var fsm : FiniteStateMachine = $StateMachine as FiniteStateMachine
 @onready var flowers : Flowers = get_parent()
+@onready var sprite : Sprite2D = $Sprite
 
 var enabled : bool = false
 var eating : bool = false