Feat(Core): ExternalEvent compatibility (#285)

Author: stonebuzz

CHANGELOG.md

@@ -11,6 +11,11 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 - Fix menu icon
 
+### Added
+
+- Add `External Event` for associated item types
+
+
 ## [2.13.0] - 2025-09-30
 
 ### Added

setup.php

@@ -64,7 +64,7 @@ function plugin_init_tag()
             ],
             __('Assistance')     => [
                 'Ticket', 'Problem', 'Change', 'TicketRecurrent',
-                'TicketTemplate',
+                'TicketTemplate', 'PlanningExternalEvent',
             ],
             __('Management')     => [
                 'Budget', 'Supplier', 'Contact', 'Contract', 'Document',