User defined template folder cannot be changed

Describe the bug
The setting for the template direcotry under yournextcloud.com/settings/user/richdocuments does not do anything. It seems that only a folder with the name "Templates" in your root direcotry is used as template folder.

To Reproduce
Steps to reproduce the behavior:

1. Make sure you have a folder "Templates" in your root directory with some odt/ods/odp documents in there.
2. Create a new office document
3. See how the dialog lets you select a template of the ones you have in your template folder
4. Go to settings/user/richdocuments and click the delete button behind the template directory input
5. Repeat steps 2-3 - nothing changed, although the template directory setting should deleted
6. Go to your home directory in Nextcloud files and rename the folder "Templates" to "XYZ"
7. Create a new office document
8. See how there is no template selection dialog displayed
9. Go to settings/user/richdocuments and change the template directory to your renamed folder "XYZ"
10. Create a new office document
11. See how there is no template selection dialog displayed - nothing changed, although the template directory should have been changed

Expected behavior
The setting for the template directory should let you control freely which folder to use as the template directory or unset the usage of the folder as the template directory.

Enhancement: It would be nice if internally the folder ID is used instead of the path, so the directory setting doesn't get broken when the folder is moved or renamed.

Nextcloud version:
28.0.3

Version of the richdocuments app
8.3.2

Version of Collabora Online
COOLWSD 23.05.9.2

Start by reproducing the behavior from settings/user/richdocuments with a Templates folder, then test deleting, renaming, and selecting a different folder before tracing the setting and template-selection entry points. Done means the selected folder controls available templates and clearing the setting disables template selection; moving or renaming the folder should not break it if the folder ID enhancement is included.