A preview call can be quite expensive and cause timeout in a cluster. As a short term fix we identified 2 (hopefully) small fixes:

- make the call cancellable, the main issue here seems to be that preview calls search without using a parent task id(see this fix for data feeds: https://github.com/elastic/elasticsearch/pull/88142/files#diff-aba58244cb8f9dfa3ac3b6efeb02259e3d5956576f56c1ff5e243dd2aac27381)
- pass the timeout parameter of the preview call to the search call, currently a timeout can be specified, but is ignored for the inner search call, which is executed with no timeout (see https://www.elastic.co/guide/en/elasticsearch/reference/master/search-search.html#search-search-api-query-params).

Both changes are bugs and shall be relatively simple to implement and considered for backport to the 7.17 branch.

@przemekwitek can you have a look at this?

related: #88010
x-pack/plugin/transform/src/main/java/org/elasticsearch/xpack/transform/transforms/Function.java
Map<String, String> headers,
        SourceConfig sourceConfig,
        Map<String, String> fieldTypeMap,
        int numberOfRows,
        ActionListener<List<Map<String, Object>>> listener
    );
    /**
     * Get the search query for querying for initial (first checkpoint) progress
     *
     * @param searchSourceBuilder a searchsource builder instance
     * @return the searchSource, expanded with the relevant parts
     */
    SearchSourceBuilder buildSearchQueryForInitialProgress(SearchSourceBuilder searchSourceBuilder);
    /**
     * Process the search response from progress search call and return progress information.
     *
     * @param response the search response
     * @param progressListener listener that takes the progress information as call back
     */
    void getInitialProgressFromResponse(SearchResponse response, ActionListener<TransformProgress> progressListener);
    /**
     * Validate the configuration.
     *
     * @param listener the result listener
     */
    void validateConfig(ActionListener<Boolean> listener);
    /**
     * Returns names of fields that are critical to achieve good transform performance.
     * Such fields should ideally be indexed, not runtime or script fields.
     *