chore: reconcile contribution rules and onboarding fixtures

Extract the guided setup test fixture without dropping cases. Supply current settings/discovery contracts and Opus 5.5 in the isolated Storybook boundary.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

.github/workflows/docker-runner-check.yml

@@ -177,8 +177,6 @@ jobs:
         run: |
           set -uo pipefail
           pnpm install --frozen-lockfile --ignore-scripts
-          # Historical evaluation fixtures read these exact public trees.
-          # Fetch only their objects; keep the selected checkout unchanged.
           git fetch --no-tags --depth=1 origin 2a8a99e4a5f69aa803b3f10b982f583e75a87042 16ef1a5744b23bb043a8b286e6288921da1de98f
           status=0
           for check in 'pnpm -r typecheck' 'pnpm test:run' 'pnpm check:token-gates' 'pnpm test:e2e:runner:typecheck' 'pnpm test:e2e:runner:unit' 'pnpm build' 'if [ -f scripts/verify-grok-npm-install.mjs ]; then node scripts/verify-grok-npm-install.mjs; fi'; do