*
 * Use [INSTANCE] for a task runner that uses daemon threads. There is not currently a shared
 * instance for non-daemon threads.
 *
 * The task runner is also responsible for releasing held threads when the library is unloaded.
 * This is for the benefit of container environments that implement code unloading.
 *
 * Most applications should share a process-wide [TaskRunner] and use queues for per-client work.
 */
class TaskRunner(

=== ":material-language-kotlin: Kotlin"
    ```kotlin
      class UploadProgress {

        companion object {

    /** Whether to use pipelines for document processing */
    protected boolean usePipeline = false;

    /**
     * Adds an index configuration file path to be loaded.
     *
     * @param path path to the index configuration file
     */
    public void addIndexConfig(final String path) {
        indexConfigList.add(path);
    }

    /**