Group the recipe menu

The skill's just menu goes from 73 lines to 12, one per [group]. No recipe is renamed or removed. just lab default <group> lists a group with docs. The docs point at the menu, and the README names just 1.31.

contrib  read        dupcheck search clone rebase lint-message docs-lint danger-spec
contrib  draft       docs-mr apply-suggestions draft
lab      rig         up down status disks ssh ssh-cmd env-names dev-image license
lab      ai          aigw real-model plugin seed
lab      dap         dap-bootstrap enable-flow enablement-check verify-self-hosted trigger-preflight trigger-flow reset rails-config
lab      dap steps   dap-onboard enable-flags seed-flows self-hosted-model ai-settings group-project enable-flows sync-flow verify
lab      check       doctor network-check playwright validate drift-check
lab      runners     duo-runner-register ci-runner-register runner-docker-auth runner-tls-ca
lab      search      advanced-search advanced-search-status exact-code-search exact-code-search-status search-probe
lab      shapes      hotpatch openshift-local https-private-ca two-plane geo openshift
lab      airgap      airgap-probe airgap-mirror airgap-seal airgap-unseal airgap-verify
A group with docs: just <module> default <group>