Promote the Lighthouse Workflow into the Reference Implementation

[BrettReifs]

Question

What production work is required to promote the accepted Lighthouse Workflow and its chosen scene and export contracts into the Project Extension while preserving the security, deterministic correctness, accessibility, test, design-lint, and review gates established by this map?

[BrettReifs]

Implementation must emit and accept only the flat canonical integer JSON form of fourier-path/v2; no alternative packed or base64 coefficient encoding belongs in the Reference Implementation.