### Description

Only "search hits" based queries (no aggregations) provide a consistent view on the data when paginating through the result set. With point-in-time, it is possible to support transactional semantics for aggregation queries as well.

This issue is somewhat blocked by https://github.com/elastic/elasticsearch/issues/75528 because a PIT can not immediately be closed if the aggregation result set contains less than `fetch_size` records. This could cause some increased resource utilization due to open PITs. Especially if the client does not close the SQL cursor.
x-pack/plugin/sql/qa/server/src/main/java/org/elasticsearch/xpack/sql/qa/rest/RestSqlTestCase.java
import org.elasticsearch.client.Request;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.Response;
import org.elasticsearch.client.ResponseException;
import org.elasticsearch.common.CheckedSupplier;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.bytes.BytesArray;
import org.elasticsearch.common.io.Streams;
import org.elasticsearch.core.Nullable;
import org.elasticsearch.core.Tuple;
import org.elasticsearch.test.NotEqualMessageBuilder;
import org.elasticsearch.test.VersionUtils;
import org.elasticsearch.xcontent.XContentBuilder;
import org.elasticsearch.xcontent.json.JsonStringEncoder;
import org.elasticsearch.xcontent.json.JsonXContent;
import org.elasticsearch.xpack.sql.proto.CoreProtocol;
import org.elasticsearch.xpack.sql.proto.Mode;
import org.elasticsearch.xpack.sql.proto.StringUtils;
import org.elasticsearch.xpack.sql.qa.ErrorsTestCase;
import org.hamcrest.Matcher;
import org.junit.After;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.sql.JDBCType;
import java.time.Instant;
import java.time.ZoneId;
import java.time.ZonedDateTime;