### 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
String mode = randomMode();
        String sqlRequest = query("SELECT DATE_PART('TZOFFSET', date) AS tz FROM " + indexPattern("test_date_timezone") + " ORDER BY date")
            .timeZone(zoneId.getId())
            .mode(mode)
            .fetchSize(2)
            .toString();
        String cursor = null;
        for (int i = 0; i <= datetimes.length; i += 2) {
            Map<String, Object> expected = new HashMap<>();
            Map<String, Object> response;
            if (i == 0) {
                expected.put("columns", singletonList(columnInfo(mode, "tz", "integer", JDBCType.INTEGER, 11)));
                response = runSql(new StringEntity(sqlRequest, ContentType.APPLICATION_JSON), "", mode);
            } else {
                assertNotNull(cursor);
                response = runSql(
                    new StringEntity(cursor(cursor).mode(mode).toString(), ContentType.APPLICATION_JSON),
                    StringUtils.EMPTY,
                    mode
                );
            }
            List<Object> values = new ArrayList<>(2);
            for (int j = 0; j < (i < datetimes.length - 1 ? 2 : 1); j++) {
                values.add(
                    singletonList(
                        ZonedDateTime.ofInstant(Instant.ofEpochMilli(datetimes[i + j]), zoneId).getOffset().getTotalSeconds() / 60
                    )
                );
            }
            expected.put("rows", values);