Adds new calendar link permission (#504)

Updates group permissions schema to include support for managing group instance calendar links, enabling more granular control over calendar access settings.

Author: Miner28

openapi/components/schemas/GroupPermissions.yaml

@@ -26,6 +26,7 @@ enum:
   - group-roles-assign
   - group-roles-manage
   - group-calendar-manage
+  - group-instance-calendar-link
 x-enum-varnames:
   - group_all
   - group_announcement_manage
@@ -51,4 +52,5 @@ x-enum-varnames:
   - group_members_viewall
   - group_roles_assign
   - group_roles_manage
-  - group_calendar_manage
+  - group_calendar_manage
+  - group_instance_calendar_link