Task 6: getSearchFields() client fn + SearchField type in api/search.ts,
and the useSearchFields() hook in builder/rules/fieldCatalog.ts that
reshapes the catalog into fieldTypes (name -> FieldType) and byGroup
views for the rule builder (Tasks 7-8).
Generated SearchFieldResponseModel has all-nullable fields (name/label/
type/group/values), unlike the brief's non-null assumption -- adapted by
dropping fields with a null name and defaulting group to 'Other' / type
to 'text' rather than indexing under undefined.
timothy
30a8f67e8e