Data Science Python Stack

Opinionated stack — one library per job, organized into four tiers plus an orthogonal agent feature:

1. Mandatory — installed at project start, no exceptions.
2. User choice (competing-library jobs) — multiple valid libraries for the same job; the user picks via AskUserQuestion before any import lands.
3. Optional — install only when the project's task requires it.
4. Transitive — already pulled in by the mandatory tier; do not install explicitly, but know they're available.
5. Agent feature (orthogonal) — deps that the agent uses to audit a workspace and to power the editor LSP integration (ipython, pyright), kept out of the production-shape runtime via a manager-specific scope. Install logistics owned by python-env-manager § "Agent feature"; consumed by audit-ml-pipeline and the opencode LSP integration.