feat(pwa): favicon, maskable icon, splash screens, runtime cache, safe-area insets

- Add favicon.ico, favicon-32x32.png, favicon-16x16.png
- Add dedicated maskable-512x512.png with safe-zone padding for Android adaptive icons
- Add iOS splash screens for 5 common device sizes (excluded from SW precache)
- Add NetworkFirst runtime caching for stable API routes (excludes volatile endpoints)
- Add safe-top inset to all view headers for PWA standalone mode
- Bump version to 0.2.2

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

vite.config.ts

@@ -26,7 +26,7 @@ export default defineConfig({
         icons: [
           { src: '/pwa-192x192.png', sizes: '192x192', type: 'image/png' },
           { src: '/pwa-512x512.png', sizes: '512x512', type: 'image/png' },
-          { src: '/pwa-512x512.png', sizes: '512x512', type: 'image/png', purpose: 'maskable' },
+          { src: '/maskable-512x512.png', sizes: '512x512', type: 'image/png', purpose: 'maskable' },
         ],
         shortcuts: [
           {
@@ -39,7 +39,7 @@ export default defineConfig({
         categories: ['developer-tools', 'productivity'],
       },
       injectManifest: {
-        globPatterns: ['**/*.{js,css,html,ico,png,svg,woff2}'],
+        globPatterns: ['**/*.{js,css,html,ico,svg,woff2}', '*.png', 'mascot/*.png'],
       },
     }),
   ],