doc

Use for ANY operation on a doc under docs/ — creating, updating/editing, changing its status, or querying. Keeps the YAML front matter (title/status/type/updated) correct and regenerates the docs/README.md wiki index. Invoke when the user says 'new doc', 'create a doc/design/RFC', 'start a design doc', 'update the doc', 'edit this doc', 'mark this doc done/in-review', 'change the doc status', or asks 'which docs are…