Get Schemas

Every publicly visible schema with its identity, summary and counts.

Response: {"schemas": [{schema, organization, country, acronym, summary, dataset_count, series_count, has_series_tables}], "tables": TABLE_REFERENCE, "example_sql": str, "counted_at": str | null}

dataset_count is the number of datasets loaded in the database when that has been computed (see _db_dataset_counts), else the number described in the catalog metadata; any schema still on the metadata figure is queued for a background warm.