Bulk glTF conversion

[jwnimmer-tri]

Per https://github.com/RobotLocomotion/drake/issues/20935, we want nearly all of our models to use gltf (not obj) for visual meshes.

Note that proximity meshes (if any?) should not be converted to gltf.

All gltfs with png file should also have ktx2 textures available (gltf-used but not gltf-required).

This ticket will track the conversion process:

• [x] allegro hand #62
• [x] #58
• [x] dishes #62
  • [x] Waiting on #60
• [x] franka_description #62
  • Converted, but they can be replaced by Anzu's as we see fit. If we do so, confirm with legal.
• [x] #36
• [x] jaco_description #62
• [x] manipulation_station and realsense2_description #62
• [x] pr2_description #62
  • This model is not used by Drake. The only testing required is just to run model_visualizer.
• [x] skydio_2 #62
  • Just add the gltf for now (and switch this repo's urdf to cite it). Don't delete the obj yet -- we have a deprecated URDF file in Drake that will continue to refer to the obj until 2024-05-01.
• [x] tri_homecart
• [x] ur_description #62
  • Instead of converting the obj, should we just use the Anzu gltfs for this? (If yes, also need to run by TRI legal first.)
• [x] veggies #62
  • [x] Waiting on #60
  • Converted locally. Consider replacing it with Anzu gltfs.
• [x] wsg_50_description #62
• [x] #45

[jwnimmer-tri]

Hallelujah!

[jwnimmer-tri]

franka_description: Converted, but they can be replaced by Anzu's as we see fit.

FYI this was submitted as #66.