refactor(enemy): 小怪选招改用 WeightedPick 共享原语(权重缓冲复用,零 GC)

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

@@ -10,9 +10,14 @@ namespace BaseGames.Enemies.Abilities
     public sealed class EnemyAttackSelector
     {
         private readonly List<IAttackCandidate> _candidates;
+        // 权重缓冲区（与 _candidates 等长，每次选招复用）：避免每次选招 new List 造成 GC
+        private readonly List<float> _weightBuf;
 
         public EnemyAttackSelector(IEnumerable<IAttackCandidate> candidates)
-            => _candidates = new List<IAttackCandidate>(candidates);
+        {
+            _candidates = new List<IAttackCandidate>(candidates);
+            _weightBuf  = new List<float>(_candidates.Count);
+        }
 
         public int Count => _candidates.Count;
 
@@ -47,22 +52,19 @@ namespace BaseGames.Enemies.Abilities
 
         private IAttackCandidate SelectByWeight(bool hasLOS, bool grounded)
         {
-            float total = 0f;
+            // 有效权重：不合格候选填 0（由共享原语保证零权重项绝不被选中）。缓冲区复用 → 选招零 GC。
+            _weightBuf.Clear();
             for (int i = 0; i < _candidates.Count; i++)
             {
                 var c = _candidates[i];
-                if (Eligible(c, hasLOS, grounded)) total += Mathf.Max(0f, c.Weight);
+                _weightBuf.Add(Eligible(c, hasLOS, grounded) ? Mathf.Max(0f, c.Weight) : 0f);
             }
-            if (total <= 0f) return SelectByPriority(hasLOS, grounded); // 权重全 0 → 退化为按 Priority 选(并列取首个)
-            float roll = Random.value * total;
-            for (int i = 0; i < _candidates.Count; i++)
-            {
-                var c = _candidates[i];
-                if (!Eligible(c, hasLOS, grounded)) continue;
-                roll -= Mathf.Max(0f, c.Weight);
-                if (roll <= 0f) return c;
-            }
-            return null; // 理论不达（浮点边界兜底）
+
+            int idx = BaseGames.Core.WeightedPick.Index(_weightBuf);
+            if (idx >= 0) return _candidates[idx];
+
+            // 无正权重（合格候选权重全 0）→ 退化为按 Priority 选(并列取首个)
+            return SelectByPriority(hasLOS, grounded);
         }
     }
 }