Decodes federated /multi-search responses into per-index raw maps suitable
for building the public search result structs returned from Scrypath.search/3.
Federated responses carry a flat hits list tagged with _federation.indexUid
and optional facetsByIndex keyed by index UID. This module never calls
String.to_atom/1 on remote keys.
Summary
Functions
Returns {:ok, [{schema, raw_map}]} aligned to indexed_schemas declaration order.