FQ/BUG: Shared Links within Teamfolders break when the user who created them gets deactivated/deleted

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Steps to reproduce

Prerequituses
Set Up "Groupfolder 1"
Set up User A
Have Both Of them in "Group 1"

1. As user A > Create a file in "Groupfolder 1" and create a public link for it.
2. As "anonymous User from the Web" > Open the link in a new browser to chek if its working (it is)
3. As "Nextcloud Administrator" deacitvate/delete User A

Expected behaviour

Link from Step 2. shall still be valid and Working

Actual behaviour

Link is no longer Valid ("Site not found")

Server configuration

Operating system:
Linux 6.8.0-87-generic x86_64
Web server:

Database:
mysql
Version: 10.11.15

PHP version:
8.3.27
Nextcloud version: (see Nextcloud admin page)
Nextcloud Hub 10 (31.0.10)

Team folders version:
Version 19.1.12

Updated from an older Nextcloud/ownCloud or fresh install:
fresh install

Where did you install Nextcloud from:
Hoster

Are you using external storage, if yes which one: local/s3/smb/sftp/...
no
Are you using encryption: yes/no
no
Are you using an external user-backend, if yes which one: LDAP/ActiveDirectory/Webdav/Saml/...
no

Client configuration

Browser:
FF / Opera
Operating system:
Windows

Logs

No files or tests are named in the issue. Reproduce the Team folders public-link flow with a user who is then deactivated or deleted, and trace the link handling to determine why access changes; done means the existing link remains valid afterward.