pre-commit hooks (mirror husky + lint-staged)

[ulises-jeremias]

Summary

Local git hooks for Ruff/format/basic checks.

CNA mapping

CNA: .husky/ + .lintstagedrc.json + prepare script.

Acceptance criteria

• .pre-commit-config.yaml with ruff + end-of-file + trailing whitespace
• Install instructions in CONTRIBUTING

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