v0.1.0 — first release

First release of mcp-nixreview: a safety gate for agent-proposed NixOS configuration changes. An MCP server (FastMCP, Streamable HTTP) that grades security-relevant NixOS config deltas (HIGH/MED/LOW), attests the closure against a cached CISA KEV catalog via vulnix, gates on a human decision, and writes an append-only, hash-chained (tamper-evident) audit ledger with a verify_ledger check. 8 tools. Advisory, not authoritative (curated regex matcher, not a Nix evaluator; vulnix coarse matching) — see the README MVP-limitations table and network-exposure note. Hardened Docker: pinned digest, hash-pinned requirements.lock, non-root, read-only rootfs, no-new-privileges; CI runs ruff + import smoke + 19 pytest + Trivy.