stac-fastapi now supports the collection search extension! https://github.com/stac-utils/stac-fastapi/pull/736 To enable this extension in stac-fastapi-pgstac we need to expose the `collection_search` function in pgstac: https://github.com/stac-utils/pgstac/blob/3ba567c27cbdb26f7654611df29504d04a73136a/src/pgstac/migrations/pgstac.0.9.1.sql#L4030-L4097