fix(runtime): preserve hidden setposition collision ownership

tests/AcDream.Runtime.Tests/Physics/RuntimeSetPositionStateTests.cs

@@ -113,6 +113,42 @@ public sealed class RuntimeSetPositionStateTests
         Assert.Equal(1, ownership.PreparedMoverCount);
     }
 
+    [Theory]
+    [InlineData(PhysicsStateFlags.Hidden)]
+    [InlineData(PhysicsStateFlags.Hidden | PhysicsStateFlags.NoDraw)]
+    public void HiddenObjectCommitsResidenceWhileSuppressingCollisionReports(
+        PhysicsStateFlags suppressedState)
+    {
+        PhysicsEngine engine = FlatEngine(SourceLandblock, 0f);
+        using var lifetime = new RuntimeEntityObjectLifetime(engine);
+        RuntimeEntityRecord record = CreateRecord(lifetime, 0x70001022u, 1);
+        PhysicsStateFlags state = PhysicsStateFlags.Gravity | suppressedState;
+        PhysicsBody body = AttachBody(lifetime, record, SourceCell, state);
+        var collisionObserver = new CollisionReportObserver();
+        using IDisposable collisionSubscription = lifetime.Physics
+            .CollisionReports.Subscribe(collisionObserver);
+
+        RuntimeSetPositionOutcome outcome = lifetime.Physics.SetPosition.Apply(
+            record,
+            record.PositionAuthorityVersion,
+            Command(Request(SourceCell, new Vector3(12f, 18f, 7f))));
+
+        Assert.Equal(
+            RuntimeSetPositionStatus.CommittedHostAcknowledgementPending,
+            outcome.Status);
+        Assert.True(body.InWorld);
+        Assert.Equal(SourceCell, record.FullCellId);
+        Assert.Equal(new Vector3(12f, 18f, 7f), body.Position);
+        Assert.True(lifetime.Physics.IsSpatialRoot(record));
+        Assert.Empty(collisionObserver.Reports);
+        RuntimeCollisionReportingOwnershipSnapshot reporting = lifetime
+            .Physics.CollisionReports.CaptureOwnership();
+        Assert.Equal(0, reporting.OwnerCount);
+        Assert.Equal(0, reporting.PendingSetPositionDispatchCount);
+        Assert.True(lifetime.Physics.SetPosition.AcknowledgeProjection(
+            outcome.Projection));
+    }
+
     [Fact]
     public void PublicPlacementChannelObservesRetriesAndAcknowledgesExactToken()
     {
@@ -2582,6 +2618,15 @@ public sealed class RuntimeSetPositionStateTests
         }
     }
 
+    private sealed class CollisionReportObserver
+        : IRuntimeCollisionReportObserver
+    {
+        internal List<RuntimeCollisionReport> Reports { get; } = [];
+
+        public void OnCollisionReport(in RuntimeCollisionReport report) =>
+            Reports.Add(report);
+    }
+
     private sealed class EntityObserver : IRuntimeEntityObjectObserver
     {
         internal List<RuntimeEntityDelta> Deltas { get; } = [];