integration discussion - ORCID

[ORCID](https://orcid.org) is a website where academic researchers can publish a short bio, list their publications and so on. It would be nice to use it as well as a place where proofs can be published.

Differently from other "identity" services like Facebook, ORCID is quite open:
- it is run by a non-profit organization with a diffuse board of directors;
- most the source code that runs behind the scenes is on GitHub (MIT licence);
- has a public API.

Start by reviewing issue #402 and ORCID's public API to determine what integration is being proposed. The issue names no repository files, tests, or concrete behavior; a useful next step is to define the proof workflow, affected entry points, and acceptance criteria before implementation.

Written by the indexing model from the issue text.