game: add weapon active ability

scenes/weapons/weapon_sword_projectile.gd

@@ -4,7 +4,7 @@ extends Node2D
 @export var speed: float = 500.0
 @export var range: float = 200.0
 @export var target: Node2D
-@export var damage: float
+@export var damage_mult: float = 1.0
 @export var on_hit_sig: Signal
 
 var _direction: Vector2
@@ -36,5 +36,5 @@ func _physics_process(delta: float) -> void:
 func _on_area_2d_body_entered(body: Node2D) -> void:
 	if body in _already_hit:
 		return
-	on_hit_sig.emit(self, body)
+	on_hit_sig.emit(self, body, damage_mult)
 	_already_hit.append(body)