Return the SQL schema for all DS queries in request (to provide information to AI / Autocomplete for SQL expressions).
All DS queries are treated as if they were inputs to SQL expressions in terms of conversion, regardless if they are selected in a query or not.
Requires feature toggle queryService = true
Endpoint is apis/query.grafana.app/v0alpha1/namespaces/default/sqlschemas
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Co-authored-by: Todd Treece <360020+toddtreece@users.noreply.github.com>
