spec-closelisted

# Close a Spec Post-merge bookkeeping: confirm a shipped spec is really done and retire it, so the queue and the docs reflect reality. Runs after the owner accepts and `git-merge-pr` lands the change. `spec-execute-next` invokes this in its reset for merged specs; it also runs standalone. ## Steps 1. Resolve the spec. Confirm it actually shipped: its PR is `MERGED` (`gh pr view <pr> --json state,mergedAt`) and the plan's `## Work steps` are fully ticked. Not merged or steps unticked - STOP and report; it is not done. 2. Ensure the docs reconciliation landed in the merged change (`spec-execute` Phase D): the feature doc reflects the new behavior, durable rules and decisions were extracted. If anything is missing, **apply it now** (via `spec-document`) - the feature doc is the durable record, the spec is not; never close on stale docs. 3. `autonomous` mode: set `status: completed` with the date. `supervised` mode: write nothing - fully ticked steps plus the merged PR already read as `completed` (`spec-discipline`). 4. Archive per the project convention (learn from shipped specs): keep the numbered folder (default), move to `specs/_archive/`, or delete the plan file if the project deletes shipped plans. Never lose the record silently. 5. Report: spec closed, where it was archived, the feature doc(s) it updated. ## Verify - PR merged and work steps ticked confirmed; the durable feature doc carries the shipped behavior; autonomous - `status: completed` written. ## Scope / ha