Refactor code structure for improved readability and maintainability

Assets/_Game/Scripts/Enemies/Abilities/AppearAbility.cs

@@ -0,0 +1,25 @@
+using System.Collections;
+using Animancer;
+using UnityEngine;
+
+namespace BaseGames.Enemies.Abilities
+{
+    /// <summary>
+    /// 出场演出能力：播放出场动画后切换到 Combat 阶段（适用于小Boss或需出场动画的精英怪）。
+    /// 可复用于任何"播出场动画→进入战斗"的敌人。
+    /// </summary>
+    public class AppearAbility : EnemyAbilityBase
+    {
+        [SerializeField] private ClipTransition _appearClip;
+
+        protected override IEnumerator ExecuteCoroutine()
+        {
+            Phase = AbilityRunState.Active;
+            if (_appearClip.Clip == null) yield break;
+
+            _animancer.Play(_appearClip);
+            yield return EnemyAbilityWaits.Get(_appearClip.Clip.length);
+            _enemy.SetAiPhase(AiPhase.Combat);
+        }
+    }
+}