refactor(武器系统): 重构武器冷却和攻击逻辑

- 将CooldownTimer的startCooldown方法重命名为更简洁的start
- 为EntityBase添加weaponStore节点管理武器
- 修改武器攻击逻辑，现在由Weapon类自身处理冷却和攻击
- 调整武器卡片的UI布局和描述居中显示
- 为Rooster角色添加预设武器

scripts/Structs/Weapon.gd

@@ -24,11 +24,14 @@ signal selected(applied: bool)
 @onready var costsBox: GridContainer = $"%costs"
 @onready var selectButton: Button = $"%selectBtn"
 
+var cooldownTimer = CooldownTimer.new()
+
 func _ready():
 	selectButton.pressed.connect(
 		func():
 			apply(UIState.player)
 	)
+	cooldownTimer.cooldown = cooldown
 	rebuildInfo()
 func _physics_process(_delta: float):
 	descriptionLabel.text = buildDescription()
@@ -76,7 +79,7 @@ func buildDescription():
 	var result = descriptionTemplate
 	for key in store.keys():
 		result = result.replace("$" + key, "[color=cyan]%.1f[/color]" % readStore(key))
-	return result
+	return "[center]%s[/center]" % result
 func readStore(key: String, default: Variant = null):
 	return store.get(key, default)