Robot descriptions v2.15.1

Robot descriptions v2.15.1

Adds simulated views from MSG's existing msg_camera for Solid and Soft TPU jaws. The previews use the unchanged open-jaw orange-box grasp fixtures, with brighter demo headlighting. Images are native 1280 x 720 renders at the model's 51.5-degree vertical FOV, without cropping, camera reorientation or geometry changes.

The camera guide and both PNGs are bundled in all six arm/MSG packages. Product guides link to them, and the MSG guide embeds both views. The guide includes a Python rendering example, the URDF camera/optical frame names, and a clear distinction between modeled views and real camera calibration.

Corrects old PAR6 appearance notes that said 90 degrees. No model camera settings, kinematics, geometry, collision shapes, masses, inertias or controls change. CC BY 4.0 model licensing and Apache-2.0 support-code licensing are retained.

Eight independent model ZIPs, the review PDF, manifest and SHA256SUMS are included. SSG48 standalone packages contain no camera.