[Chore] Add lint and test automation (CI/CD)

[moakilodash]

Problem

The repo has no automated quality gate for the new Python stack. Contributors can't be sure their code meets the project's standards before opening a PR.

Proposed Change

Set up GitHub Actions (or similar CI) to run unit tests and basic Python linting on every pull request. Failing checks should block merges into dev.

Acceptance Criteria

• GitHub Actions workflow runs on PRs to dev and master
• Workflow runs pytest and reports coverage
• Workflow runs a linter (e.g., flake8, black) and reports style issues
• Failing tests or lint errors block merge
• README or CONTRIBUTION.md includes local commands to run the same checks
• CI runs in under 2 minutes for typical PRs

Related

See ROADMAP.md Phase 6 - Production Readiness

Contributor Lane: Testing & Tooling (Issue 7/2)
Difficulty: Easy-Medium
Related Phase: Phase 6 - Production Readiness