feat(icons): redesign app icon with updated shapes and colors

- Replace book illustration with a centered document icon
- Update color palette to use deeper blue tones
- Redesign the bookmark and overlay elements for a cleaner look
- Adjust icon proportions and spacing for better visual balance

package.json

@@ -7,7 +7,8 @@
     "dev": "vite",
     "build": "tsc && vite build",
     "preview": "vite preview",
-    "tauri": "tauri"
+    "tauri": "tauri",
+    "icon": "cp app-icon.svg public/app-icon.svg && cp src-tauri/icons/32x32.png public/favicon.png"
   },
   "dependencies": {
     "@base-ui/react": "^1.5.0",