feat: styled offline page with app install hint, bump versions

Replace bare offline fallback with styled page matching the app's
design (glass nav, dark/light mode, wifi-off icon, retry button).
Add hint to install Android APK or PWA for offline use.

Site: 1.0.0 → 1.1.0
Android/Tauri: 0.1.0 → 0.2.0

package.json

@@ -1,6 +1,6 @@
 {
 	"name": "homepage",
-	"version": "1.0.0",
+	"version": "1.1.0",
 	"private": true,
 	"type": "module",
 	"scripts": {