improve repository structure in openvocab orga
https://github.com/openvocab
- seem not used or needed: membership, role, place, group, person, core
- ovn - makes sense as general workspace focused on putting all other elements together
- holodex - rename to agent? while I find it a cool name, for most people it will make no sense. also brings confusion with https://github.com/holodex
- exchange - makes sense to me as one of ovn sub workstreams, for example IPO tables experiment might ignore this part and focus just on process