The sovereign blocks build_03 composes from.

Each block renders in its own test harness with mock data, no app shell, no signals (Constitution P-01, P-04). This page is the development entry to build_03; it is not the app. The app composition layer (L2 + L3 per RD-031) is Phase C work. Build_02 remains preserved at cleopatra-1gc.pages.dev.