[Feature] Update 3D model of the ARNEIS conveyor

[alv67]

Closes #45

📑 Description

✅ Checks

• [x] My pull request adheres to the code style of this project
• [ ] My code requires changes to the documentation
• [x] I have updated the documentation as required
• [x] All the tests have passed

ℹ Additional Information

[gmacario]

@alv67 is there any chance that mocs/project/README.md may be published somewhere under https://arneis.readthedocs.io/ ?

[gmacario]

@alv67 is there any chance that mocs/project/README.md may be published somewhere under https://arneis.readthedocs.io/ ?

It looks like the answer is "no". Let's merge as-is, then...