Update media attachment results to link to their parent post

searchwp-customisations.php

<?php

add_filter( 'searchwp_live_search_results_entry_data', function( $data, $result ) {
    if ( $result instanceof \WP_Post && $result->post_type === 'attachment' ) {

        $parent_id = wp_get_post_parent_id( $result->ID );

        if ( $parent_id ) {
            $data['permalink'] = get_permalink( $parent_id );
        }
    }
    return $data;
}, 20, 2 );