The highest uidNumber was cached in dal/ldap_max_uid_file. That breaks
with more than one replica and is lost on every container restart. The
uniqueness check behind it searched base '' (the root DSE), which
OpenLDAP never matches, so nothing caught a stale file. The error path
also referenced a setting that does not exist.
Now a paged search over ENTIRE_SEARCH_BASE finds the highest uidNumber
on each activation. Numbering is unchanged: the next number is above
both LDAP_DEFAULT_START_UID and every existing uidNumber.
LDAP_MAX_UID_FILE_PATH is no longer used.