fix(motion): restore retail object manager order

Process animation completion at the retail process_hooks boundary, then run targeting, movement, PartArray completion, and PositionManager in the named UpdateObjectInternal order for local, remote, hidden, and position-less animated objects. Retire TS-42 with deterministic conformance coverage.\n\nCo-authored-by: OpenAI Codex <codex@openai.com>

tests/AcDream.Core.Tests/Physics/RetailObjectManagerTailTests.cs

@@ -0,0 +1,38 @@
+using AcDream.Core.Physics;
+
+namespace AcDream.Core.Tests.Physics;
+
+public sealed class RetailObjectManagerTailTests
+{
+    [Fact]
+    public void Run_UsesNamedRetailManagerOrder()
+    {
+        var calls = new List<string>();
+
+        RetailObjectManagerTail.Run(
+            checkDetection: () => calls.Add("detection"),
+            handleTargeting: () => calls.Add("target"),
+            movementUseTime: () => calls.Add("movement"),
+            partArrayHandleMovement: () => calls.Add("part-array"),
+            positionUseTime: () => calls.Add("position"));
+
+        Assert.Equal(
+            ["detection", "target", "movement", "part-array", "position"],
+            calls);
+    }
+
+    [Fact]
+    public void Run_SkipsMissingManagersWithoutDuplicatingNeighbours()
+    {
+        var calls = new List<string>();
+
+        RetailObjectManagerTail.Run(
+            checkDetection: null,
+            handleTargeting: () => calls.Add("target"),
+            movementUseTime: null,
+            partArrayHandleMovement: () => calls.Add("part-array"),
+            positionUseTime: null);
+
+        Assert.Equal(["target", "part-array"], calls);
+    }
+}