canon: rotate METAPAT to primitive structure/action v3

[erinepshovel-code]

Rotates METAPAT from canon v2 to proposed canon v3.

Core changes:

• Thing -> Boundary -> State -> Simplex as root structure.
• Relate / Emerge / Vector as action.
• Scalar / Transformation / Time / Energy as measurement/result.
• Tensor becomes structure produced when simplexes relate; energy becomes derived rather than primitive.
• Every domain exposes some properties of Platonic energy; no domain exposes all.
• Cross-domain recurrence is tested by removing domain-specific implementation rather than importing a domain as root.
• Chapter Zero remains the authoritative textbook Chapter 0 source.

This PR intentionally fails closed on stale v2 consumers/fixtures until they are explicitly migrated. No v2 binding is silently rebound.