[Bug]: CalDavBackend->getChangesForCalendar() reports move operation events (added, deleted) on wrong calendars #40051

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

CalDavBackend->getChangesForCalendar() reports move operation events (added, deleted) on wrong calendars

Moved calendar object from calendar 26 (Combined) to 24 (Personal). Then ran CalDavBackend->getChangesForCalendar() on both.

Results:

Calendar 24 (Personal) shows delete event but should show added

$this->LocalStore->getChangesForCalendar(24, 132, null, null)
array(4)
    syncToken: 134  
    added: array(0)
    modified: array(0)
    deleted: array(1)
        0: "9ED4BC5B-EE08-4E02-8E49-B341CF5C7E64.ics"

Calendar 26 (Combined) shows added event but should show deleted

$this->LocalStore->getChangesForCalendar(26, 32, null, null)
array(4) 
    syncToken: 33  
    added: array(1)  
        0: "9ED4BC5B-EE08-4E02-8E49-B341CF5C7E64.ics"  
    modified: array(0)  
    deleted: array(0)  

Steps to reproduce

1. Move event between two calendars
2. Execute CalDavBackend->getChangesForCalendar() on each calendar

Expected behavior

Report move operation events (added, deleted) on proper calendar

Installation method

None

Nextcloud Server version

26

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.2

Web server

Nginx

Database engine version

MySQL

Is this bug present after an update or on a fresh install?

None

Are you using the Nextcloud Server Encryption module?

None

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

No response

List of activated Apps

No response

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

No response