Emails are not sent when adding a recipient after an appointment has been created

Steps to reproduce

1. Create a calendar.
2. Add some attendees.
3. Save the meeting.
4. Click on the meeting, and now add a new attendee. When you do this, no email is sent to the newly added user.

Expected behavior

No email is sent to the attendee who is added after the calendar has been created in the first stage.

Actual behavior

It should send an email to the attendees you add to the event after it has been created.

Calendar app version

5.0.6

CalDAV-clients used

none

Browser

Chrome latest and Firefox latest

Client operating system

Linux mint

Server operating system

Debian

Web server

Nginx

Database engine version

MariaDB

PHP engine version

PHP 8.2

Nextcloud version

30.0.2

Updated from an older installed version or fresh install

Fresh install

List of activated apps

Nextcloud configuration

This is not important

Web server error log

nothing in here.

Log file

Browser log

Additional info

No response

No source files or tests are named. Start by reproducing the attendee-update flow in the calendar app and trace how notifications are triggered when an existing event gains a recipient. Done means a newly added attendee receives the expected email without changing notifications for existing attendees.