docs: align flagship presentation surface

[HarperZ9]

Summary

• add the current source version and an evidence-bounded status section to the README
• keep the operator command reference below the five-minute value demonstration
• harden LSP staleness detection when Windows preserves metadata for same-length edits
• add an Unreleased changelog entry

Verification

• python -m pytest -q tests (full suite passed)
• git diff --check

AI-assisted contribution. Please review the LSP change and README placement before merge.