[Feature Request] Calendar invites by email / ischedule backend

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Request

I understand that monica is more for a personal content management but with the introduction of caldav, it would be nice to also be able to send calendar invitations to other people.
I am unsure how hard/complicated this is and I couldn't find any issues directly addressing this (from a brief search) so my apologies if this has already been considered and dropped as a feature.

So far, very few CalDav servers have server side sending of invites.
DAViCal relies on user side calendar to send out invitations, such as with lightning, thunderbirds calendar.
NextCloud does have a server side sending of emails but IIRC it uses a centralized to send out invites and not from the users email address.

Another possibility of doing this is by supporting the ischedule support for calendars, so that invites can be managed by calendar backends.
This is described in RFC 6638 - https://tools.ietf.org/html/rfc6638
It has partial support in DAViCal, and it would be nice to see this more widely supported.

Let me know if I can help provide more information.

Thanks a lot,
Aisha