feat(vfx): port retail hidden and teleport presentation

Preserve canonical live-object ownership across Hidden transitions and remote teleport placement so effects, collision, streaming, and targeting remain synchronized.

tests/AcDream.App.Tests/Rendering/EntityPhysicsHostTests.cs

@@ -0,0 +1,65 @@
+using System.Numerics;
+using AcDream.App.Rendering;
+using AcDream.Core.Physics;
+using AcDream.Core.Physics.Motion;
+
+namespace AcDream.App.Tests.Rendering;
+
+public sealed class EntityPhysicsHostTests
+{
+    [Fact]
+    public void NotifyHidden_FansNonOkStatusAndClearsWatcherSubscription()
+    {
+        const uint watcherId = 0x50000001u;
+        const uint targetId = 0x70000001u;
+        var hosts = new Dictionary<uint, IPhysicsObjHost>();
+        var watcherUpdates = new List<TargetInfo>();
+
+        EntityPhysicsHost watcher = CreateHost(
+            watcherId,
+            hosts,
+            watcherUpdates.Add);
+        EntityPhysicsHost target = CreateHost(targetId, hosts, _ => { });
+        hosts.Add(watcherId, watcher);
+        hosts.Add(targetId, target);
+        watcher.SetTarget(0u, targetId, 1f, 0.1);
+        watcherUpdates.Clear();
+
+        target.NotifyHidden();
+
+        TargetInfo hidden = Assert.Single(watcherUpdates);
+        Assert.Equal(TargetStatus.ExitWorld, hidden.Status);
+        Assert.Null(watcher.TargetManager.TargetInfo);
+        Assert.False(target.TargetManager.VoyeurTable!.ContainsKey(watcherId));
+
+        watcherUpdates.Clear();
+        watcher.SetTarget(0u, targetId, 1f, 0.1);
+
+        TargetInfo restored = Assert.Single(watcherUpdates);
+        Assert.Equal(TargetStatus.Ok, restored.Status);
+        Assert.Equal(targetId, restored.ObjectId);
+        Assert.True(target.TargetManager.VoyeurTable.ContainsKey(watcherId));
+    }
+
+    private static EntityPhysicsHost CreateHost(
+        uint id,
+        IReadOnlyDictionary<uint, IPhysicsObjHost> hosts,
+        Action<TargetInfo> update)
+    {
+        return new EntityPhysicsHost(
+            id,
+            getPosition: () => new Position(
+                0x01010001u,
+                new Vector3(id == 0x50000001u ? 0f : 2f, 0f, 0f),
+                Quaternion.Identity),
+            getVelocity: () => Vector3.Zero,
+            getRadius: () => 0.5f,
+            inContact: () => true,
+            minterpMaxSpeed: () => 1f,
+            curTime: () => 1.0,
+            physicsTimerTime: () => 1.0,
+            getObjectA: objectId => hosts.GetValueOrDefault(objectId),
+            handleUpdateTarget: update,
+            interruptCurrentMovement: () => { });
+    }
+}