THE SPECTRAL SIEVE Addendum: Open Problems, Hidden Structures, and Hard Lemma Progress

This addendum consolidates all results produced in the most recent programme session. It is organised in four parts: (A) resolution of open problems P3, P4, P7, and P11; (B) hidden structures found in the resolved results; (C) Heisenberg, Poincare, and Renormalisation Group analysis of those structures; and (D) the Hard Lemma progress report, including the key new variational theorem and the corrective finding about the zero gap ordering.