- runner.go: store fingerprints in local var, call formatter.SetFingerprints() instead of mutating caller's *Config; removes Fingerprints field from Config - fingerprint.go: use singleflight.Group in Query to coalesce concurrent probes for the same IP, eliminating the double-probe race - output layer: add SetFingerprints(map[string]string) to Formatter interface; textFormatter and jsonFormatter each hold their own fingerprints field - formatter_test.go: add TestTextFormatterWriteSummaryShowsVersions and TestJSONFormatterWriteSummaryShowsVersions verifying version output Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: multica-agent <github@multica.ai>