refactor(update): cut over the frame orchestrator

Reduce GameWindow.OnUpdate to one typed orchestration call and remove transitive window callbacks from teardown, liveness, teleport placement, live presentation, auto-entry, and entity packet routing. Preserve the frozen retail object/network order while making the production owner graph explicit and testable.

src/AcDream.App/World/LiveWorldOriginState.cs

@@ -1,3 +1,5 @@
+using System.Numerics;
+
 namespace AcDream.App.World;
 
 /// <summary>
@@ -40,6 +42,23 @@ internal sealed class LiveWorldOriginState
         CenterY = centerY;
     }
 
+    public (int X, int Y) GetCenter() => (CenterX, CenterY);
+
+    /// <summary>
+    /// Converts the streamed render frame back into retail's landblock-local
+    /// physics frame at the one placement seed boundary.
+    /// </summary>
+    public Vector3 CellLocalForSeed(Vector3 worldPosition, uint cellId)
+    {
+        int landblockX = (int)((cellId >> 24) & 0xFFu);
+        int landblockY = (int)((cellId >> 16) & 0xFFu);
+        var origin = new Vector3(
+            (landblockX - CenterX) * 192f,
+            (landblockY - CenterY) * 192f,
+            0f);
+        return worldPosition - origin;
+    }
+
     /// <summary>
     /// Ends the accepted-origin lifetime while retaining the last coordinates
     /// as the next placeholder. Consumers must gate them on