arch(retort): define org-meta skill sourcing and placement strategy

[JustAGhosT]

Summary

Consolidates two Baton-only architecture tasks into one GitHub tracker:

• Baton b2059c5d: decide shippability strategy for org-meta-sourced skills
• Baton a401eba1: write skill placement policy for org-meta vs scope: project vs consuming repo

Problem

Retort is not fully standalone while many skills are sourced from ~/repos/org-meta/skills/<name>/SKILL.md. At the same time, contributors do not have a written policy for deciding whether a skill or specialist agent belongs in org-meta, Retort itself, or a consuming repo overlay.

Scope

• Decide how org-meta-sourced skills become shippable for clean-machine and CI use.
• Define the universal-vs-specialist placement rule for skills and agents.
• Document the chosen model in an ADR or short engineering policy.
• Update .agentkit/spec/skills.yaml comments or adjacent docs so source: org-meta, source: retort, and project-scoped skills have clear intent.

Acceptance criteria

• ADR or engineering policy captures the sourcing and placement decision.
• Policy includes a short decision checklist contributors can use in review.
• source: org-meta semantics are unambiguous after the decision lands.
• Follow-up implementation/audit tickets are created if the chosen strategy requires more work.

Source

Created during Baton/GitHub consolidation on 2026-07-07 from Baton tasks b2059c5d and a401eba1.