FM1503/dsh-ui-layout

Declares a UI layout contract, measures pages in headless Chrome or Godot scenes and declared layouts, and audits overlap, occlusion, overflow, clipped text, undersized targets, dead controls, spacing drift and z-order traps, with a breakpoint matrix and a sidebar panel. Page measurement needs Chrome, Edge or Chromium and the puppeteer-core package installed where the DSH profile can resolve it; Godot scenes and declared layouts need neither.