- Installed Playwright and Storybook packages
- Created playwright.config.ts with viewport matrix and browser configurations
- Installed Playwright chromium browser
- Created e2e/viewport-matrix.spec.ts for viewport matrix testing
- Created e2e/horizontal-overflow.spec.ts for horizontal overflow testing
- Added test scripts to package.json (test:e2e, test:e2e:ui, test:e2e:viewport, test:e2e:overflow)
- Updated LAUNCH_READY_UI_UX_ROADMAP.md checklist with testing infrastructure status