Replace this folder's `icon.svg` with a proper designed icon, then export PNGs:

  /apps/web/public/icon-192.png  (192x192)
  /apps/web/public/icon-512.png  (512x512)

The manifest.json references these. The PWA install prompt won't show until both PNGs exist.

For Phase 1 dev, the SVG placeholder is fine. Use any tool (Figma, Inkscape) to export
192 and 512 PNGs from the SVG. Optional: add a 32x32 favicon.ico.