spec-cancellisted

# Cancel a Spec Retire a spec that will not ship - the owner dropped it, scope changed, or another spec replaces it - without losing why. A cancelled spec is a recorded decision, not a deleted file. In supervised mode `cancelled` is the one status the pipeline ever writes (`spec-discipline`): an abandoned spec looks exactly like one nobody started, and this skill is what tells them apart - never a human editing the frontmatter. A re-pull does not revive a cancelled spec; the source item gets a fresh one, and the folder stays as the record. ## Steps 1. Resolve the spec. Read it enough to state what it was for. 2. Determine reason and mode: `cancelled` (will not be done) or `superseded by NNN` (another spec replaces it). The reason is required. 3. If an open branch / PR exists for the spec, note it - the owner decides whether to close the PR; this skill does not delete pushed work. 4. Set `status: cancelled` (or `status: superseded by NNN`, with both linked) plus a one-line reason and the date in the spec's front page. 5. Reconcile any draft docs the spec left behind (via `spec-document`): a stubbed feature doc or an inferred rule that describes behavior which never shipped is removed or clearly marked not-shipped - never leave orphan docs implying a change that did not land. 6. Archive per project convention - default: keep the folder with the cancelled status. Never silently delete; the record of "we decided not to" is itself valuable. 7. Report: spec retired, reason, supe