Use this when the user asks about lookalike, look-alike, typosquat or impersonation domains of their domain, or whether someone has registered a name close to theirs. DNS-only: checks the closest variants of the name and returns facts — how many resolve and how many accept mail, with up to ten resolving names (each with the kind of variant, whether it accepts mail, and same_infra when it points at the domain's own nameservers or mail servers, which usually means the owner registered it defensively). Never a verdict: relay the names as facts and never call one malicious — resolving only means the name is registered and answers. A name that could not be checked counts as unknown, never as free, and complete is false while any name is unknown. Unregistered names are never listed. If the user wants these names re-checked over time, call start_monitoring_signup.