Capability set for AshClickhouse.DataLayer.
ClickHouse supports the filtered, projected, limited reads required by the AshDyan engine. AshDyan still formats rows in memory so output semantics do not depend on ClickHouse-specific grouped query results.
ClickHouse's native aggregate support is broader than this capability list; the list describes AshDyan analysis types, not the data layer's aggregate API. Percentiles and histograms remain bounded in-memory computations.