LFIS–16: Completeness of Foundational Structure

LFIS–16 proves the relative completeness of the foundational representational constraint taxonomy used in the Light Frame Infrastructure Series. Building on LFIS–13 through LFIS–15, the volume shows that the present primitive language enumerates all local closure classes, multi-ray admissibility classes, demand effects, and outcome types needed for the foundational block. The central result is that every representational context reduces to one of two outcomes: routed closure, where at least one closure obligation remains, or completion, where no closure obligation remains locally. The proof also establishes that triangle loop constraints generate all loop constraints in the K6 closure graph, so no independent higher-order loop obstruction is required within the present primitives. LFIS–16 is explicitly a relative completeness theorem: it closes the existing LFIS primitive constraint language without claiming that no enlarged future primitive language could introduce additional structures.