feat: Implement Room Streaming System

- Add RoomStreamingManager to manage room loading and unloading based on player proximity.
- Create StreamingBudgetConfigSO for memory and performance budgeting of the streaming system.
- Introduce TransitionDirector to handle seamless and atmospheric fade transitions between rooms.
- Develop WorldGraph to represent room connectivity and facilitate neighbor queries and distance calculations.
- Implement RoomNode and RoomEdge classes to structure room data and connections.

Assets/_Game/Scripts/Enemies/AI/BD_IsHPBelow.cs

@@ -1,4 +1,4 @@
-#if GRAPH_DESIGNER
+#if GRAPH_DESIGNER
 using Opsive.BehaviorDesigner.Runtime.Tasks;
 using Opsive.BehaviorDesigner.Runtime.Tasks.Conditionals;
 using BaseGames.Enemies;
@@ -9,22 +9,24 @@ namespace BaseGames.Enemies.AI
     /// BD Conditional：Boss HP 是否低于阈值（用于触发阶段切换）。
     /// HPThreshold 为 0~1 归一化比例（如 0.5 = HP ≤ 50%）。
     /// </summary>
+    [TaskName("Is HP Below Threshold?")]
+    [TaskCategory("BaseGames/Enemy/State")]
+    [TaskDescription("检查当前 HP 是否低于指定百分比阈值")]
     public class BD_IsHPBelow : Conditional
     {
+        [UnityEngine.Range(0f, 1f)]
         [UnityEngine.SerializeField] private float m_HPThreshold = 0.5f;
 
         private EnemyBase _enemy;
 
-        public override void OnStart()
-        {
-            _enemy = GetComponent<EnemyBase>();
-        }
+        public override void OnAwake() => _enemy = GetComponent<EnemyBase>();
 
         public override TaskStatus OnUpdate()
         {
             if (_enemy == null || _enemy.Stats == null) return TaskStatus.Failure;
 
-            float ratio = (float)_enemy.Stats.CurrentHP / _enemy.Stats.MaxHP;
+            float maxHP = UnityEngine.Mathf.Max(1f, _enemy.Stats.MaxHP);
+            float ratio = (float)_enemy.Stats.CurrentHP / maxHP;
             return ratio <= m_HPThreshold ? TaskStatus.Success : TaskStatus.Failure;
         }
     }