### Description

This is to investigate what we could do to support the data streams in SQL. The backing indices can be queried already, but to address them similarly as they're queried over QDSL one would need to construct a pattern learned out of band and not through SQL metadata discovery mechanisms.
x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/index/IndexResolver.java
);
    public static final IndicesOptions FIELD_CAPS_FROZEN_INDICES_OPTIONS = new IndicesOptions(
        EnumSet.of(Option.ALLOW_NO_INDICES, Option.IGNORE_UNAVAILABLE),
        EnumSet.of(WildcardStates.OPEN)
    );
    private static final String UNMAPPED = "unmapped";
    private final Client client;
    private final String clusterName;
    private final DataTypeRegistry typeRegistry;
    private final Supplier<Set<String>> remoteClusters;
    public IndexResolver(Client client, String clusterName, DataTypeRegistry typeRegistry, Supplier<Set<String>> remoteClusters) {
        this.client = client;
        this.clusterName = clusterName;
        this.typeRegistry = typeRegistry;
        this.remoteClusters = remoteClusters;
    }
    public String clusterName() {
        return clusterName;
    }
    public Set<String> remoteClusters() {
        return remoteClusters.get();
    }
    /**
     * Resolves only the names, differentiating between indices and aliases.
     * This method is required since the other methods rely on mapping which is tied to an index (not an alias).
     */
    public void resolveNames(
        String clusterWildcard,
        String indexWildcard,
        String javaRegex,