Agent Skills: tdd-typescript

TypeScript/JavaScript Test-Driven Development with Vitest, strict red-green-refactor methodology, domain-first modeling (DDD) via branded types, principled DRY discipline, React component testing, and comprehensive coverage patterns. Use when implementing TypeScript features with TDD, writing Vitest tests, testing React components, developing with test-first approach, modeling domain concepts, refactoring duplication, or when user mentions 'TypeScript TDD', 'Vitest', 'React testing', 'JavaScript TDD', 'red-green-refactor', 'TypeScript unit tests', 'branded types', 'value object', 'ubiquitous language', 'DRY', or 'test-driven TypeScript'.