Include linkages between branches

[cmungall]

There may be implicit linkages between branches - these should be made explicit

e.g model performs task

This should be aligned with definitions - ideally definitions should refer to terms in this ontology or other ontologies

this could also be a useful way to group things other than is-a. E.g. LLMs and Markov Models may live in different subhierarchies but they would be united by next token prediction