Add ruff and mypy to dev dependencies with configuration in pyproject.toml.
Add a lint CI job that runs ruff check, ruff format --check, and mypy.
Auto-fix import sorting and formatting across the codebase. Exclude
alembic/versions from linting (auto-generated migrations). Ignore B008
(FastAPI Depends pattern) and RUF001 (unicode in user-facing strings).
21 ruff lint errors and 50 mypy errors remain for manual review.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
