Refactor rhythm action architecture

scenes/characters/character.gd

@@ -131,3 +131,13 @@ func start_directional_air_attack(direction: Vector2) -> void:
 	attack_time_left = air_attack_duration
 	attack_lunge_time_left = air_attack_lunge_duration
 	velocity = Vector2(attack_x * air_attack_lunge_speed, 0.0)
+
+
+func begin_attack_motion(duration: float, next_velocity: Vector2) -> void:
+	attack_lunge_time_left = maxf(0.0, duration)
+	velocity = next_velocity
+
+
+func stop_attack_motion() -> void:
+	attack_lunge_time_left = 0.0
+	velocity = Vector2.ZERO