- Add Playwright (Chromium) for E2E tests with webServer auto-start - Add Vitest + @testing-library/react + coverage-v8 with 80% threshold - Add smoke E2E spec and jest-dom setup file - Update turbo.json with test:e2e task - Enforce 80% coverage rule in AGENTS.md (global testing policy) - Add full Testes section to docs/conventions/frontend.md - Add tasks.md for scenario-creator feature (14 tasks, T01–T14) Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>