Scaffolds, audits, and tests Storybook stories for React (web) and React Native / Expo (native) component libraries. Generates three artefacts in two files per invocation: a visual regression `*.stories.tsx` file holding a `Default` story (variants grouped into one snapshot) and a `Playground` story (interactive `args` / `argTypes`), plus a sibling `*.test.stories.tsx` interaction test under a `/Tests` namespace. Supports an opt-in, per-pathname auth flow whose credentials live in the OS keychain, never in the repo. The iteration loop drives the Playwright CLI against the running Storybook URL; visual evidence delegates to the `pr-reviewer` agent and the `screen-recorder` skill. An opt-in `--validate` phase drives Playwright adversarially against the rendered story, then fixes what it breaks behind a confidence gate. Triggers on "scaffold stories", "add storybook", "story for this component", "interaction test for this story", "validate this story", "/storybook".