[Bug]: Recurring calendar events get ignored in free/busy display when trying to schedule a new event

⚠️ 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

When trying to schedule a new calendar event, recurring events are not shown as "busy" times in the time selector; meanwhile, one-off events from the same CalDAV calendar do get shown as "busy" blocks.

Steps to reproduce

1. Subscribe to a CalDAV calendar
2. Create a new event on your main calendar
3. Get to the "Choose time" dialog
4. One-off events from the CalDAV calendar will be shown as "busy" time blocks, recurring events however will not.

Expected behavior

Recurring events should be shown as "busy" time blocks as well.

Nextcloud Server version

29

Operating system

Other

PHP engine version

PHP 8.3

Web server

Nginx

Database engine version

PostgreSQL

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

Fresh Nextcloud Server install

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

List of activated Apps

Nextcloud Signing status

Nextcloud Logs

Additional info

No response