GitLab

Adds MIT license template, machine-readable CITATION.cff, structured metadata
directory, pytest test scaffold, and three new docs (DATA_MANAGEMENT.md,
PIPELINE_CONVENTIONS.md, R_SETUP.md). Restores 3 readiness audit checks
(license-file, citation-file, metadata-dir) and expands required docs to 8.
Total enforced checks: 19.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>