91f7a02f2c
Parameterize used strings.ReplaceAll, so an external host that merely
ends with the zone name as a substring (e.g. "notreconops.ru." against
zone "reconops.ru") was falsely rewritten to "not{{domain_name}}.".
Replace only where the zone name sits on a DNS-label boundary (start/
end of string or a non-alphanumeric/hyphen character), and resolve to
a fixed point so adjacent occurrences sharing a single boundary
character are still both replaced.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>