Search runs. Each matched run expands to one grouping per data source attached to the run:
asset-typed data sources contribute one grouping per data scope on the asset; dataset-typed
data sources contribute one grouping per dataset. Every grouping is tagged by runRid and
dataScope (the asset’s data scope name for asset-typed sources, or the run-local data
source ref name for dataset-typed sources); asset-typed groupings additionally carry
assetRid.