Consider support for/interfacing with LinkML

[lu-pl]

LinkML is (among other things) a sort of YAML-based unified constraint language, implementing e.g. shape subclassing and an import system able to fetch remote LinkML shapes.

LinkML is (at least) as expressive as SHACL as a constraint language and supports derivation of SHACL graphs and GraphQL configs from LinkML YAML definitions - it may therefore be very well possible to use LinkML as a single source of truth for any modern Semantic Application.

Also: LinkML tooling is natively implemented in Python!

One cool idea for a future rdfproxy feature would be to implement logic for deriving rdfproxy-compliant SPARQL queries and respective Pydantic models from a LinkML YAML source.

In the best case, this would allow to auto-generate a full rdfproxy-based backend from a LinkML definition.