[codex] Add license and minimal CI

[VatsalGoel3]

Summary

• add an MIT license so the public repo is clearly reusable
• add a minimal GitHub Actions workflow that runs python -m pytest -q on push and pull_request
• remove the unused seaborn dependency noise from the package metadata
• keep the release/version story honest at 0.1.0

Testing

• python -m pytest -q

Notes

• no model, metric, or results changes
• version remains 0.1.0 intentionally; I plan to tag the public release as v0.1.0, not v1.0.0