uv-managed PEP 621 project with ruff, mypy (strict on packages/domain and packages/llm), pytest with coverage, and import-linter contracts that mechanically enforce the dependency rules of 架构文档 §4.2 -- including the two forbidden edges (compliance and identity must not depend on business domains). CI, pre-commit and a detect-secrets baseline gate every push; .env is gitignored before anything is ever staged.