The spec the M11 arc (M11.1–M11.5) implements; all five CHANGELOG
entries reference it. Status header updated from "post-v1.0 design
draft, no code" to an implementation map against the arc, so the
landed doc is not self-contradictory. Design body unchanged; the
"Open questions" remain open by design.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
