Meta Query

Invisible element that runs a data query and exposes data, loading, and error selectors for other elements on the page.

• A page needs a query result no visible element already loads — e.g. a KPI count, a lookup, or an aggregate used by several expressions.
• Two or more elements should share the same query result instead of each fetching it independently.
• It is typically created under the hood by other templates when they need shared query data.

Points at a view/query via dataSource.queryName, optionally with a fixed filter expression and a response format. It renders nothing; failures only surface when another element reads its error selector.