Ship a raster (PNG) app icon — SVG-only favicon fails Ray-Ban Display QA and PWA install #9

Problem

The app ships only an SVG icon. The Meta Ray-Ban Display Web App Simulator QA checklist fails on this:

Favicon present and not SVG → SVG favicon detected

StepView scores 4/5 in the simulator, and this is the only failing check. Display/glasses environments don't reliably render SVG favicons, and PWA installability expects raster icons.

Evidence

• index.html: <link rel="icon" href="favicon.svg" type="image/svg+xml"> — SVG only.
• manifest.json: icons contains a single entry { "src": "favicon.svg", "sizes": "any", "type": "image/svg+xml" } — no PNG, so no installable raster icon.

Expected

A raster (PNG) icon is present so the RBD QA check passes and the PWA has proper install icons.

Suggested fix

• Add raster icons to the repo: favicon-192.png and favicon-512.png (generated from the existing favicon.svg).
• In index.html, reference a PNG (keep the SVG as an alternate):
  <link rel="icon" type="image/png" sizes="192x192" href="favicon-192.png">
• In manifest.json, add PNG entries with real sizes:
  { "src": "favicon-192.png", "sizes": "192x192", "type": "image/png", "purpose": "any" } and a 512x512 ("purpose": "any maskable").