Add cupertino_icons dependency

navigation.dart imports package:flutter/cupertino.dart for
CupertinoPageTransition, which made the asset bundler warn that the
CupertinoIcons font was expected but missing. Declaring cupertino_icons
provides the font and clears the warning; it tree-shakes away in release
builds since no Cupertino icons are actually rendered.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/pubspec.lock

@@ -145,6 +145,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.0.2"
+  cupertino_icons:
+    dependency: "direct main"
+    description:
+      name: cupertino_icons
+      sha256: "41e005c33bd814be4d3096aff55b1908d419fde52ca656c8c47719ec745873cd"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.0.9"
   dbus:
     dependency: transitive
     description:

frontend/pubspec.yaml

@@ -24,6 +24,9 @@ dependencies:
   firebase_core: ^3.8.0
   firebase_messaging: ^15.1.6
   flutter_local_notifications: ^18.0.1
+  # Used via package:flutter/cupertino.dart (CupertinoPageTransition); also
+  # provides the CupertinoIcons font the asset bundler expects to be present.
+  cupertino_icons: ^1.0.8
 
 dev_dependencies:
   flutter_test: