Reproducibility Checklist + Pinning

# Reproducibility Checklist + Pinning (Flagship Standard) Complete this checklist on your own repo. The flagship gate (m5-l16) re-runs this exact checklist cold — every miss below is a gate failure there. ## The checklist 1. Pinned dependencies (`requirements.txt` with `==`, Python version pinned). 2. `.dockerignore` present (no `.git`, data, secrets in the image). 3. `Dockerfile` builds from a cold clone with zero manual steps. 4. Random seeds fixed and logged (train split, model init, sampling). 5. Data version recorded (checksum + source URL, train/holdout split hash). 6. One-command smoke run: `docker build . -t app && docker run app pytest -q`. 7. No secrets in code or image (env-only; verified by scanning the build log). 8. Run-comparison note: 3 runs logged in the tracker with params + metrics. ## GCP parity note Same checklist on Cloud Run: image from Artifact Registry, env via Secret Manager. Checklist items are identical; only the deploy target changes.