pytest + coverage thresholds (mirror c8 gates)

[ulises-jeremias]

Summary

Workspace-wide pytest discovery with coverage floors.

CNA mapping

CNA: test:all + c8 thresholds (~59–60%).

Acceptance criteria

• [tool.pytest.ini_options] testpaths = ["packages"]
• Coverage config with initial thresholds (can start lower, document target parity)
• Example smoke test in each stub package

Blocked by

none

Blocks

none

Reference

Parity matrix (workspace): knowledge/create-python-app-parity-matrix.md
Reference repo: https://github.com/Create-Node-App/create-node-app

Parent epic

#3