[masarray]

P5 — Beginner-first public README without losing engineering history

Follows P2 hardening #744 (base main merge commit 2449e2b).

• Clarifies first-screen product positioning: free/open-source IEC 61850 Communication Validation & Client Testing tool; starts from actual IED IP or SCL.
• Moves five historical release-milestone sections from the 32 KB main README into docs/RELEASE_MILESTONES_ARCHIVE.md verbatim; preserves the original version context and links to CHANGELOG / release artifacts.
• Keeps current v1.6.42 screenshot gallery, download links, Quick Start, trust boundary, architecture, actual capabilities, and full historical evidence discoverable.
• Avoids two confusing top-level Quick Start headings by naming the deeper step-by-step section 'Engineering walkthroughs'.
• Adds release-milestone archive to docs/README.md navigation and clarifies SECURITY.md that tagged public stable and gated main source can differ.

Boundaries: README/docs/security wording only. No application/engine/runtime changes, binary/tag/update ledger changes, P2 rollback, or #729 source-gate bypass.

Please validate exact-head Windows CI, source-clean license/security boundaries, README image/link integrity, and repository rendering.

[chatgpt-codex-connector]

Codex Review Summary

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Review	Status	Commit	Review trigger
📝 Code Review	🔄 Running since 2026-10-25T08:59:32.910880Z	e8bb435	PR opened

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[masarray]

P5 repository metadata follow-up (read-only audit, not modified by this PR)

GitHub About currently says: Open-source IEC 61850 engineering workstation for MMS, reporting, GOOSE, file transfer, Sampled Values, SCL, diagnostics, and Smart Control.

Suggested concise public About copy: Free open-source IEC 61850 client tester for communication validation, IED discovery, MMS, Reporting, GOOSE, SMV, SCL and FAT/SAT evidence.

Current topics include an apparent typo protection-relat and capability-like tags iec61850-server / iec61850-simulator that should be reviewed for accurate product-facing positioning. Recommend fixing typo to protection-relay and retaining only topics backed by the actual shipped application role. Do not remove legitimate simulator support by assumption.

The available GitHub connection exposes repository settings as read-only; this PR does not claim the GitHub About or topic metadata have been edited. The README/docs changes are real and independently CI-tested.