Add a UI/UX design phase (/define-design, /update-design) and a platform
app generation phase (/generate-app web|flutter|winui3) to the workflow,
positioned between /setup-project and /add-feature.
- commands: define-design, generate-app, update-design
- add-feature: check docs/design/ before implementation; update design
files first when a feature changes the UI
- skills: ui-design, design-tokens, platform-ui-generation
- docs/design/ structure documented (source of truth = ui-blueprint.json;
SVGs are references only; generated UI follows design-tokens.json)
- README and AGENTS.md updated with the new workflow
