add hitting projectile function

scripts/projectiles/projectile.gd

@@ -1,5 +1,5 @@
 class_name Projectile
-extends Area3D
+extends AnimatableBody3D
 
 @export var _collision_debug_material: Material
 
@@ -18,7 +18,7 @@ func _ready() -> void:
 	global_position = _start_position
 
 
-func _process(delta: float) -> void:
+func _physics_process(delta: float) -> void:
 	if _life_timer <= 0:
 		queue_free()
 
@@ -30,3 +30,7 @@ func init(velocity: Vector3, start_position: Vector3, lifetime: float = 10) -> v
 	_velocity = velocity
 	_start_position = start_position
 	_lifetime = lifetime
+
+
+func set_velocity(velocity: Vector3) -> void:
+	_velocity = velocity