Add nonces for security

dry up redundencies

includes/class-hssm-slides-cpt.php

@@ -928,7 +928,7 @@ class HSSM_Slides_CPT {
     public function ajax_update_slide_order() {
         // Verify nonce and permissions
         if ( ! wp_verify_nonce( $_POST['nonce'], 'hssm_update_slide_order' ) || ! current_user_can( 'edit_posts' ) ) {
-            wp_die( 'Unauthorized' );
+            wp_send_json_error( 'Unauthorized' );
         }
         
         if ( isset( $_POST['slide_ids'] ) && is_array( $_POST['slide_ids'] ) ) {