feat: fetch structure files from Materials Project

[ycexiao]

Problem

This issue is migrated from PDF-bl/pdfbl.sequential#28. It was brought up during the beamtime preparation meeting.

Fetch structure files from the materials project

Proposed solution

[sbillinge]

Thanks @ycexiao. To add to this, an easier first target than MP is COD, but this is an exciting capability, but something we want in the future. Not immediate.