Define Discovery domain for data sources in admin panel

There are three discovery domains of data sources:

• search
• rag
• nlp

Each data-source can have multiple number of these domains: all of them, some of them, just one, or none. By default, the list is empty. Administrator should have possibility to edit the list for each data-source separately.

How to use discovery domains:

• if data-source should be discoverable on SeTA WEB UI then it should have property 'search' (i.e., corpus api)
• if data-source should be discoverable on SeTA RAG API then it should have property 'rag' (i.e., rag api)
• if data-source is used for various text processing applications then it should have property 'nlp' (should not be mixed with nlp container, there are no implemented apis at the moment)

This information is mainly used in 'search' container and its apis. I.e., it affects all containers that are using/accessing opensearch.