Replace 'carve'/'headline' throughout; reframe the front-facing docs
(README, spec drafts, related-work) to describe what the repo contains
and link to it rather than narrate the process. Process framing stays in
the decision log and the intent-comment/sep-disposition planning docs.
Live SEP-1913/SEP-2061 comments updated to match.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>