Cursor sinks into the surface after the player turns

Start in packages/xr-input/src/pointer/cursor-visual.ts, focusing on updateFromIntersection and its fallback branch. Reproduce the cursor behavior in a Meta Quest 3 WebXR session with snap turning, then verify that the cursor remains visible on object surfaces after rotation and that both intersection paths behave consistently.

Cursor sinks into the surface after the player turns

Environment

• @iwsdk/xr-input 0.5.3 (also reachable through @iwsdk/core 0.5.3)
• Meta Quest 3, browser-based WebXR session
• Locomotion enabled with turning (snap turn on the thumbstick)

Symptom

The ray cursor (the white dot drawn at the intersection point) disappears once the
player has turned.

• Enter XR and point at any RayInteractable / DistanceGrabbable object: the
  cursor is drawn correctly on the surface.
• Turn with the thumbstick, then point at the same object from the same distance:
  the cursor is gone. It reappears only when the ray grazes an edge of the object,
  which suggests it is being drawn behind the surface and depth-tested away.

Not reproducible before the first turn. In a desktop (non-immersive) session where
nothing rotates the player, it never happens.

Cause

packages/xr-input/src/pointer/cursor-visual.ts, in updateFromIntersection
(dist lines 78-86, and the same shape again in the fallback branch at 87-95):

// Build world-space orientation from +Z to world normal
this.cursor.quaternion.setFromUnitVectors(ZAxis, scratchNormal);
// Convert world orientation to xrOrigin local space
quaternionHelper.copy(this.xrOrigin.quaternion).invert();
this.cursor.quaternion.multiply(quaternionHelper);
// Offset slightly along the oriented normal to avoid z-fighting
offsetHelper.set(0, 0, this.zOffset);
offsetHelper.applyQuaternion(this.cursor.quaternion);
cursorPosition.add(offsetHelper);

Two problems, both invisible while xrOrigin.quaternion is identity:

1. The world-to-local conversion multiplies in the wrong order. Expressing a
   world rotation in a parent frame is parent⁻¹ * world, so this needs
   premultiply(quaternionHelper). multiply(quaternionHelper) computes
   world * parent⁻¹.

2. The offset is applied with a local-space quaternion but added to a
   world-space position. cursorPosition still holds
   intersection.pointOnFace (world) at that point; xrOrigin.worldToLocal is
   only called afterwards. So the offset has to be built from the world normal.

With the player rotated, the offset therefore points somewhere other than out of
the surface, and for most orientations it pushes the cursor behind the geometry.
zOffset is only 0.004, so any error of more than a few degrees is enough.

Suggested fix

// Offset along the world-space normal, while the position is still world-space
offsetHelper.copy(scratchNormal).multiplyScalar(this.zOffset);
cursorPosition.add(offsetHelper);

// Then express the orientation in xrOrigin local space
this.cursor.quaternion.setFromUnitVectors(ZAxis, scratchNormal);
quaternionHelper.copy(this.xrOrigin.quaternion).invert();
this.cursor.quaternion.premultiply(quaternionHelper);

The fallback branch needs the same treatment: derive the offset direction from
intersection.pointerQuaternion (world) before converting the orientation, and
use premultiply for the conversion.