Allow to add search links to vocabularies

[nichtich]

These are best managed in BARTOC instead of Cocoda. See https://github.com/gbv/cocoda/issues/565

[nichtich]

The data structure is:

• prefLabel (multilingual name of the link target)
• url (URL template)

Open question which JSKOS field to put them in.

[nichtich]

A search link is basically JSKOS Occurrence with prefLabel in database and the url filled out as template with {notation} or {uri}.

In addition to links based on URL templates, we can also support Occurrences API. The current API is not formally specified query parameters are:

• member or members (actually uri(s) of a concept(s))
• scheme (actualy voc)
• database
• threshold (actually limit)
• notation (not supported yet)

BARTOC could also aggregate search links into an occurrences API.

For cataloging search links we need

• database (database.preflabel).
• URL template (template?)

and/or

• Occurrences API endpoint (api)

search links for K10plus can be determined automatically via CQL key.

[nichtich]

Maybe better start by managing search links in a repository of its own to facilitate inclusion in BARTOC, Cocoda, Occurrence API and other applications.

[nichtich]

See https://github.com/gbv/occurrences-api/blob/main/links.json for a start.