The PO directory has not been found. There is a problem in your Koha installation. at /usr/share/koha/Koha/I18N.pm line 197. Related to recent removal of all PO files from codebase.
Did you grep for more occurrences of the po folder in the codebase when remvoving it ?
Please read the dedicated wiki page
https://wiki.koha-community.org/wiki/Translation_files
There is a lot of noise in the logs from this warn.
Lots of: [2023/11/17 09:03:52] [WARN] The PO directory has not been found. There is a problem in your Koha installation. at /usr/share/koha/Koha/I18N.pm line 197.