Falls back to top-level filter key resolution, then $or, then SK, then full union.
When top-level keys narrow, also intersects with $or block narrowing (if any)
and skCondition narrowing because DynamoDB ANDs them — a record must satisfy
the key condition, the top-level filter, and at least one $or block.
Falls back to top-level filter key resolution, then
$or, then SK, then full union.When top-level keys narrow, also intersects with
$orblock narrowing (if any) andskConditionnarrowing because DynamoDB ANDs them — a record must satisfy the key condition, the top-level filter, and at least one$orblock.