event: Annotated[
        str | None,
        Doc(
            """
            Optional event type name.

            Maps to `addEventListener(event, ...)` on the browser. When omitted,
            the browser dispatches on the generic `message` event.
            """
        ),
    ] = None
    id: Annotated[
        str | None,
        AfterValidator(_check_id_no_null),
        Doc(
            """

        try {
            cleanupExpiredDocuments();
        } catch (final Exception e) {
            logger.debug("Failed to cleanup expired documents in poll.", e);
        }
    }

    /**
     * Dispatches an event to all registered handlers for the event name.
     *
     * @param event the event to dispatch.
     */
    protected void dispatchEvent(final EventInfo event) {

        assertTrue(heartbeatCalled.get());
        assertTrue(cleanupCalled.get());
    }

    @Test
    public void test_poll_dispatchesEvents() {
        // Verify that poll fetches events and dispatches them
        final AtomicInteger dispatchCount = new AtomicInteger(0);
        final CoordinatorHelper helper = new CoordinatorHelper() {
            @Override
            public void sendHeartbeat() {