- Moved get_ldap_str() helper to ldap_utils.py for reuse
- Updated user_service.py to use shared helper from utils
- Updated admin.py to safely extract string values from LDAP fields
- LDAP fields can be lists, strings, or None - helper handles all cases
- Fixes sync_from_ldap_to_django and compare_ldap_django actions
- Prevents 'list' object errors when comparing or assigning LDAP fields