tdd

Applies strict Test-Driven Development with a repo-local Markdown test list (default `test-lists/<slug>.md` unless the project defines another folder), Robert C. Martin’s Three Laws, deterministic tests and stable seams (unit vs narrow integration), Arrange–Act–Assert test shape, micro-iterations, refactor proximity (production and test code), fast feedback, and git micro-commits (`test:` / `feat:` or `fix:` / `refactor:`) squashed per cycle before push. Use for test-first feature slices, strict R-G-R, or when the user asks for a tracked test list plus disciplined commits.