fix(trackerobjects): re-assert kinematic each frame in pose drive

One-shot isKinematic = true at bind isn't enough — BasisObjectSyncNetworking
Awake and ControlState both flip kinematic back to false for locally-owned
props, and ControlState fires on ownership-transfer events that can happen
long after bind. Once physics gets hold of the rigidbody between our pose
writes, Scene view samples those intermediate frames (out of step with
onBeforeRender) and flickers even when Game view (which renders right after
our write) stays clean.

Re-asserting kinematic = true each frame in OnAfterSimulateOnRender is a
single bool set per binding, cheap, and defends against any external setter
without playing whack-a-mole with every code path that touches RigidRef.

Spec updated to describe the per-frame enforcement and its motivation.

Author: towneh

Basis/Packages/com.basis.trackerobjects/REQUIREMENTS.md

@@ -135,7 +135,7 @@ Existing `BasisObjectSyncNetworking.CanNetworkSteal` is unchanged; the veto sits
 `BasisObjectSyncNetworking.ControlState` sets `Rigidbody.isKinematic = false` when the object is locally owned, so physics drives the rigidbody. With a tracker also writing the transform every render frame, the two compete and the prop jitters. To prevent this:
 
 - `TryCreateBinding` captures `pickupInteractable.RigidRef.isKinematic` and stores it on the binding.
-- It then sets `isKinematic = true` for the duration of the binding.
+- It then sets `isKinematic = true`, and the per-frame pose drive re-asserts `isKinematic = true` each frame. Re-assertion (rather than one-shot) is required because `BasisObjectSyncNetworking.Awake` and `ControlState` both set `isKinematic = false` for locally-owned props, and `ControlState` can fire after bind on ownership-transfer events. Physics moving the rigidbody between our writes shows up as Scene-view flicker even when Game view (which renders right after `onBeforeRender`) looks clean.
 - `TryRemoveBinding` restores the captured value.
 
 If the target has no `BasisPickupInteractable` or no `Rigidbody`, the kinematic toggle is skipped.

Basis/Packages/com.basis.trackerobjects/Runtime/BasisTrackerObjectManager.cs

@@ -160,6 +160,17 @@ private static void OnAfterSimulateOnRender()
                 {
                     continue;
                 }
+                // BasisObjectSyncNetworking.Awake and ControlState both flip
+                // isKinematic = false on locally-owned props, and ControlState can
+                // re-fire on ownership-transfer events long after bind. If physics
+                // touches the rigidbody between our writes, Scene view samples those
+                // intermediate frames (out of step with onBeforeRender) and flickers
+                // even when Game view stays clean. Re-asserting kinematic each frame
+                // is cheap and avoids playing whack-a-mole with every external setter.
+                if (binding.HasKinematicCaptured && binding.RigidRef != null)
+                {
+                    binding.RigidRef.isKinematic = true;
+                }
                 binding.Tracker.transform.GetPositionAndRotation(out Vector3 trackerPos, out Quaternion trackerRot);
                 binding.Target.SetPositionAndRotation(
                     trackerPos + trackerRot * binding.LocalPositionOffset,