test(report): cover negotiation telemetry artifact

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Summary

• add sshd negotiation-failure telemetry to multi-host report contract inputs
• update Markdown, JSON, and warnings CSV golden artifacts
• keep parsed event and finding counts unchanged while warning telemetry increases

Validation

• ctest --test-dir build -C Debug -R report_contracts --output-on-failure
• ctest --test-dir build -C Debug --output-on-failure
• git diff --check
• added-line privacy/secret scan