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/Physics/PlayerMovementHiddenTests.cs

@@ -0,0 +1,82 @@
+using System.Numerics;
+using AcDream.App.Input;
+using AcDream.App.Rendering;
+using AcDream.App.Rendering.Vfx;
+using AcDream.Core.Physics;
+using AcDream.Core.Physics.Motion;
+using AcDream.Core.World;
+
+namespace AcDream.App.Tests.Physics;
+
+public sealed class PlayerMovementHiddenTests
+{
+    [Fact]
+    public void TickHidden_PositionManagerMovesRootAndEffectPoseWithoutPhysicsInput()
+    {
+        const uint playerGuid = 0x50000001u;
+        const uint targetGuid = 0x50000002u;
+        const uint cellId = 0x01010001u;
+
+        var controller = new PlayerMovementController(new PhysicsEngine());
+        controller.SetPosition(Vector3.Zero, cellId, Vector3.Zero);
+
+        var hosts = new Dictionary<uint, IPhysicsObjHost>();
+        EntityPhysicsHost? playerHost = null;
+        playerHost = new EntityPhysicsHost(
+            playerGuid,
+            () => controller.CellPosition,
+            () => controller.BodyVelocity,
+            () => 0.48f,
+            () => controller.BodyInContact,
+            () => 3f,
+            () => 0.1,
+            () => 0.1,
+            id => hosts.GetValueOrDefault(id),
+            info => playerHost!.PositionManager.HandleUpdateTarget(info),
+            () => { });
+        var targetPosition = new Position(
+            cellId,
+            new Vector3(5f, 0f, 0f),
+            Quaternion.Identity);
+        var targetHost = new EntityPhysicsHost(
+            targetGuid,
+            () => targetPosition,
+            () => Vector3.Zero,
+            () => 0.48f,
+            () => true,
+            () => null,
+            () => 0.1,
+            () => 0.1,
+            id => hosts.GetValueOrDefault(id),
+            _ => { },
+            () => { });
+        hosts.Add(playerGuid, playerHost);
+        hosts.Add(targetGuid, targetHost);
+        controller.PositionManager = playerHost.PositionManager;
+        playerHost.PositionManager.StickTo(targetGuid, radius: 0.48f, height: 1.835f);
+
+        var entity = new WorldEntity
+        {
+            Id = 7u,
+            ServerGuid = playerGuid,
+            SourceGfxObjOrSetupId = 0x02000001u,
+            Position = Vector3.Zero,
+            Rotation = Quaternion.Identity,
+            ParentCellId = cellId,
+            MeshRefs = Array.Empty<MeshRef>(),
+        };
+        var poses = new EntityEffectPoseRegistry();
+        poses.Publish(entity, Array.Empty<Matrix4x4>());
+
+        MovementResult result = controller.TickHidden(0.1f);
+        entity.SetPosition(result.Position);
+        entity.ParentCellId = result.CellId;
+        Assert.True(poses.UpdateRoot(entity));
+
+        Assert.InRange(result.Position.X, 0.01f, 1.5f);
+        Assert.Equal(0f, result.Position.Z);
+        Assert.Equal(Vector3.Zero, controller.BodyVelocity);
+        Assert.True(poses.TryGetRootPose(entity.Id, out Matrix4x4 root));
+        Assert.Equal(result.Position, root.Translation);
+    }
+}