Calendar event fixes and improvements (#4690)

* fixes

* saving workspaceMemberId and personId when saving attendees

* add typing

* use Map

* improve saveMessageParticipants

* fix role type

* move logic in a service

* create new service

* use new service in calendar-event-attendee.service

* modify service to include more common logic

* add defaumt value to isOrganizer in calendar-event-attendee.object-metadata

* rename folder

* renaming

packages/twenty-server/src/engine/core-modules/calendar/timeline-calendar-event.service.ts

@@ -214,8 +214,7 @@ export class TimelineCalendarEventService {
         event.description = '';
         event.location = '';
         event.conferenceSolution = '';
-        event.conferenceLink.label = '';
-        event.conferenceLink.url = '';
+        event.conferenceLink = { label: '', url: '' };
       }
     });