Remove robot plugin from palletizing world

Remove
```

ur10_suction
ls_vgr_link

```

And add it to the robot instead

Locate the palletizing world and the associated robot configuration, then inspect where the libgz_link_attacher.so plugin is declared. Move the shown plugin configuration from the world to the robot, and verify that the palletizing setup still loads with the robot attachment behavior enabled.

Written by the indexing model from the issue text.