Frozen indices are deprecated which makes all the [SQL features supporting frozen indices](https://www.elastic.co/guide/en/elasticsearch/reference/current/sql-index-frozen.html) obsolete.

This includes:

* `index_include_frozen` request parameter in the `_sql` endpoint
* `index.include.frozen` (J|O)DBC driver settings
* `SHOW TABLES INCLUDE FROZEN` queries and the `FROZEN INDEX` kind in the corresponding response
* The `FROZEN` modifier in `FROM` clauses (as in `SELECT * FROM FROZEN archive`)

`_search` raises a deprecation warning when frozen indices are being searched with `ignore_throttled=false`. SQL could do the same when the `index_include_frozen` request parameter is set or when the `FROZEN` keyword is used.

Relates to https://github.com/elastic/elasticsearch/issues/70192
x-pack/plugin/sql/qa/server/src/main/java/org/elasticsearch/xpack/sql/qa/rest/BaseRestSqlTestCase.java
return "{" + request.toString() + "}";
        }
    }
    protected void index(String... docs) throws IOException {
        indexWithIndexName(TEST_INDEX, docs);
    }
    protected void indexWithIndexName(String indexName, String... docs) throws IOException {
        Request request = new Request("POST", "/" + indexName + "/_bulk");
        request.addParameter("refresh", "true");
        StringBuilder bulk = new StringBuilder();
        for (String doc : docs) {
            bulk.append("""
                {"index":{}}
                %s
                """.formatted(doc));
        }
        request.setJsonEntity(bulk.toString());
        provisioningClient().performRequest(request);
    }
    protected void deleteTestIndex() throws IOException {
        deleteIndex(TEST_INDEX);
    }
    protected static void deleteIndex(String name) throws IOException {
        deleteIndex(provisioningClient(), name);
    }
    public static RequestObjectBuilder query(String query) {
        return RequestObjectBuilder.query(query);
    }
    public static RequestObjectBuilder cursor(String query) {
        return RequestObjectBuilder.cursor(query);