When an in-bailiwick nameserver cannot be resolved (no glue records and iterative resolution fails), the traversal previously returned a generic RespError. This made the Results section show many identical '6.7% resulted in an error' lines and the Summary show '100% resulted in an error' — even though the domain itself may be perfectly reachable in practice via glue held by the registry. Add a new RespNSResolutionFailed response type (string: ns_error) for this specific case. Changes: - traverse/response.go: add RespNSResolutionFailed, include it in IsTerminal() and String() - traverse/traverser.go: use RespNSResolutionFailed with a descriptive ErrorMessage when ResolveNS fails in processReferral - output/stats.go: map ns_error to nameserver lookup failed in summaryTypeLabel - output/text.go: handle RespNSResolutionFailed in formatResultLine Before: Results: 6.7% resulted in an error (x15) Summary: 100% resulted in an error After: Results: 6.7% nameserver ns-a.hansenits.com.au could not be resolved (x15) Summary: 100% nameserver lookup failed Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: multica-agent <github@multica.ai>