- a Wikibase repository wants to use Properties from Wikidata, but locally defined Items
- the TermSearchInteractor underlying the wbsearchentities API module should know where to search for which kind of entity.
- Implement a TermSearchInteractor that knows a target TermSearchInteractor for each entity type. Each such underlying TermSearchInteractor is configured to access a specific wiki.
- Care must be taken that the correct ID mappings are applied when constructing the TermSearchResults.
- The UI code remains completely oblivious to federation
- we do not support searching for the same kind of entity on multiple repos, but this will likely be needed in the future.
- merging search results from different repos is tricky, because relevance scores are not comparable between instances
- Eventually, TermSearchResults should get a new field identifying the repository on which a match was found.