### Description

In [siren federate](https://siren.io/federate/) we extend the `SearchService` to create `SearchContext` instances. In 8.8 this is not possible anymore because the `createContext` method takes the `ResultsType` enum which is package private.

https://github.com/elastic/elasticsearch/blob/b640c217cccab67dce7d954bc92b6b519c102b16/server/src/main/java/org/elasticsearch/search/SearchService.java#L992-L998

In order to be able to keep on calling that method from another package, the visibility of the enum `ResultsType` should be increased to `protected`.
server/src/main/java/org/elasticsearch/search/SearchService.java
}
    private <T> void ensureAfterSeqNoRefreshed(
        IndexShard shard,
        ShardSearchRequest request,
        CheckedSupplier<T, Exception> executable,
        ActionListener<T> listener
    ) {
        final long waitForCheckpoint = request.waitForCheckpoint();
        final Executor executor = getExecutor(shard);
        try {
            if (waitForCheckpoint <= UNASSIGNED_SEQ_NO) {
                runAsync(executor, executable, listener);
                return;
            }
            if (shard.indexSettings().getRefreshInterval().getMillis() <= 0) {
                listener.onFailure(new IllegalArgumentException("Cannot use wait_for_checkpoints with [index.refresh_interval=-1]"));
                return;
            }
            final AtomicBoolean isDone = new AtomicBoolean(false);
            final TimeValue timeout = request.getWaitForCheckpointsTimeout();
            final Scheduler.ScheduledCancellable timeoutTask = NO_TIMEOUT.equals(timeout) ? null : threadPool.schedule(() -> {
                if (isDone.compareAndSet(false, true)) {
                    listener.onFailure(
                        new ElasticsearchTimeoutException("Wait for seq_no [{}] refreshed timed out [{}]", waitForCheckpoint, timeout)
                    );
                }
            }, timeout, Names.SAME);
            shard.addRefreshListener(waitForCheckpoint, new ActionListener<>() {
                @Override
                public void onResponse(Void unused) {