feat: Stage 2E physics p95, runtime videos, domain audit, device-test QR

Measure Rapier world.step p95 (~0.2 ms) on GTX 1080, record real route WebMs,
expand runtime/headless hash parity, and document permanent-domain/phone blockers.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/domain/demoPlaylist.ts

@@ -56,6 +56,14 @@ export const DEMO_PLAYLIST: PlaylistCase[] = [
     scenarioId: 'boundary_dimensions',
     expectedCategory: 'C',
   },
+  {
+    id: 'pouf_c',
+    title: 'Пуфик (мягкий)',
+    description: 'Stage 2E runtime visual — soft item → C (min/soft policy)',
+    itemId: 'SKU-005',
+    scenarioId: 'boundary_dimensions',
+    expectedCategory: 'C',
+  },
   {
     id: 'plate_d',
     title: 'Тарелка',