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/World/IRoomLifecycle.cs

@@ -0,0 +1,24 @@
+namespace BaseGames.World
+{
+    /// <summary>
+    /// 实现此接口的组件可感知房间的 Dormant / Active 生命周期切换。
+    /// <para>
+    /// <see cref="Streaming.RoomHandle"/> 在休眠或激活房间时，
+    /// 会调用场景内所有实现了此接口的组件，使其做出相应响应（关闭 AI、保存状态等）。
+    /// </para>
+    /// </summary>
+    public interface IRoomLifecycle
+    {
+        /// <summary>
+        /// 房间进入休眠时调用。实现方应关闭 AI、暂停动画、停止音效，
+        /// 以避免 Dormant 房间消耗不必要的 CPU。
+        /// </summary>
+        void OnRoomDormant();
+
+        /// <summary>
+        /// 房间被激活时调用。实现方应恢复 AI、重置状态、播放入场效果等。
+        /// </summary>
+        /// <param name="context">出生上下文，含出生点 ID 和是否为复活流程。</param>
+        void OnRoomActivate(SpawnContext context);
+    }
+}