feat(角色): 添加KukeChild角色并增强KukeMC能力

新增KukeChild角色及相关资源文件，包括贴图、场景和脚本
调整KukeMC属性，增加新攻击类型可召唤KukeChild
修改EntityBase基础逻辑，添加spawnTime属性和timeLived方法
移除Rooster.gd中未使用的heal方法

scripts/Contents/Characters/KukeChild.gd

@@ -0,0 +1,21 @@
+extends EntityBase
+
+var masterMine: KukeMC
+
+func register():
+	fields[FieldStore.Entity.MAX_HEALTH] = 25
+	fields[FieldStore.Entity.OFFSET_SHOOT] = 2
+	fields[FieldStore.Entity.MOVEMENT_SPEED] = 0.25
+	fields[FieldStore.Entity.DAMAGE_MULTIPILER] = 0.1
+	attackCooldownMap[0] = 200
+func ai():
+	PresetEntityAI.follow(self, currentFocusedBoss, 500)
+	tryAttack(0)
+	if timeLived() > 10000:
+		masterMine.tryHeal(100)
+		tryDie(null)
+func attack(type):
+	if type == 0:
+		for i in randi_range(1, 3):
+			BulletBase.generate(preload("res://components/Bullets/PurpleCrystal.tscn"), self, findWeaponAnchor("normal"), position.angle_to_point(currentFocusedBoss.position))
+			await TickTool.millseconds(randi_range(5, 25))