refactor: update branding assets and convert settings to accordion UI

- Replace SVG favicons with PNG icons from new smeshicon assets
- Add theme-aware Icon component using smeshiconlight/dark PNGs
- Refactor Settings page to use collapsible accordion sections
- Add Radix UI accordion component with animations
- Update QrCode component to use new PNG icon
- Remove old favicon.svg and nostr.json files
- Add new logo assets in resources/ and src/assets/

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

tailwind.config.js

@@ -59,7 +59,19 @@ export default {
         highlight: 'hsl(var(--highlight))'
       },
       animation: {
-        shimmer: 'shimmer 3s ease-in-out infinite'
+        shimmer: 'shimmer 3s ease-in-out infinite',
+        'accordion-down': 'accordion-down 0.2s ease-out',
+        'accordion-up': 'accordion-up 0.2s ease-out'
+      },
+      keyframes: {
+        'accordion-down': {
+          from: { height: '0' },
+          to: { height: 'var(--radix-accordion-content-height)' }
+        },
+        'accordion-up': {
+          from: { height: 'var(--radix-accordion-content-height)' },
+          to: { height: '0' }
+        }
       }
     }
   },