Adds instructions on how to position the lighthouse for manus+vive (#3496)

# Description

Adds instructions on how to position the lighthouse for manus+vive, to
resolve vive tracking quality issues that users may affect hand tracking
experience.

## Type of change

- Documentation update

## Checklist

- [x] I have read and understood the [contribution
guidelines](https://isaac-sim.github.io/IsaacLab/main/source/refs/contributing.html)
- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there
Co-authored-by: Cathy Li <yuanchenl@yuanchenl-mlt.client.nvidia.com>

docs/source/how-to/cloudxr_teleoperation.rst

@@ -409,7 +409,7 @@ Manus + Vive Hand Tracking
 
 Manus gloves and HTC Vive trackers can provide hand tracking when optical hand tracking from a headset is occluded.
 This setup expects Manus gloves with a Manus SDK license and Vive trackers attached to the gloves.
-Requires Isaac Sim >=5.1.
+Requires Isaac Sim 5.1 or later.
 
 Run the teleoperation example with Manus + Vive tracking:
 
@@ -425,6 +425,10 @@ Begin the session with your palms facing up.
 This is necessary for calibrating Vive tracker poses using Apple Vision Pro wrist poses from a few initial frames,
 as the Vive trackers attached to the back of the hands occlude the optical hand tracking.
 
+For optimal performance, position the lighthouse above the hands, tilted slightly downward.
+One lighthouse is sufficient if both hands are visible.
+Ensure the lighthouse remains stable; a stand is recommended to prevent wobbling.
+
 .. note::
 
    To avoid resource contention and crashes, ensure Manus and Vive devices are connected to different USB controllers/buses.