[Feature Request]: "Classroom mode" - Allow teachers to admin simulations of students

AiiDAlab is now used in a few courses.
In many of those courses we had some issues in which we needed Sasha to check something in the students' containers, to play their simulations (e.g., due to network issues on the HPC side), or to simply make sure that everything goes as expected.

It would be quite convenient, if teachers could do this.

One could even imagine an admin panel in which teachers see the progress of all their students' simulations.