feat(Weapon): 添加HOLD_ONCE发射类型并移除废弃属性

移除已注释掉的chargable和oneShoot属性，这些功能现在由emitType枚举控制

scripts/Structs/Weapon.gd

@@ -5,7 +5,8 @@ class_name Weapon
 enum EmitType {
 	HOLD_SHOOT,
 	CLICK_SHOOT,
-	CHARGE
+	CHARGE,
+	HOLD_ONCE
 }
 
 @export var avatarTexture: Texture2D = null
@@ -14,8 +15,6 @@ enum EmitType {
 @export var typeTopic: WeaponName.TypeTopic = WeaponName.TypeTopic.IMPACT
 @export var soulLevel: int = 1
 @export var costBeachball: int = 500
-# @export var chargable: bool = false
-# @export var oneShoot: bool = false
 @export var emitType: EmitType = EmitType.HOLD_SHOOT
 @export var store: Dictionary = {
 	"atk": 10