docs: add Mobile ID favicon set from realfavicongenerator.net

Replace the old SVG favicon with a complete set including PNG, SVG,
ICO, Apple touch icon, and web app manifest for proper cross-browser
and cross-device support.

Author: phaupt

docs/.vitepress/config.mts

@@ -16,7 +16,13 @@ export default defineConfig({
     }
   },
 
-  head: [['link', { rel: 'icon', href: '/mobileid.svg' }]],
+  head: [
+    ['link', { rel: 'icon', type: 'image/png', sizes: '96x96', href: '/favicon-96x96.png' }],
+    ['link', { rel: 'icon', type: 'image/svg+xml', href: '/favicon.svg' }],
+    ['link', { rel: 'shortcut icon', href: '/favicon.ico' }],
+    ['link', { rel: 'apple-touch-icon', sizes: '180x180', href: '/apple-touch-icon.png' }],
+    ['link', { rel: 'manifest', href: '/site.webmanifest' }],
+  ],
 
   themeConfig: {
     // https://vitepress.dev/reference/default-theme-config

docs/public/apple-touch-icon.png

@@ -0,0 +1,21 @@
+{
+  "name": "Mobile ID docs",
+  "short_name": "Mobile ID",
+  "icons": [
+    {
+      "src": "/web-app-manifest-192x192.png",
+      "sizes": "192x192",
+      "type": "image/png",
+      "purpose": "maskable"
+    },
+    {
+      "src": "/web-app-manifest-512x512.png",
+      "sizes": "512x512",
+      "type": "image/png",
+      "purpose": "maskable"
+    }
+  ],
+  "theme_color": "#ffffff",
+  "background_color": "#ffffff",
+  "display": "standalone"
+}