chore(deps): update app_links and package_info_plus to latest major versions

Upgrade packages:
- app_links: ^6.1.4 → ^7.0.0 (backward compatible with v6)
- package_info_plus: ^8.0.0 → ^9.0.0 (build tooling only, no Dart API changes)

Bump Android build tooling to latest Flutter 3.38-compatible versions:
- AGP: 8.9.1 → 8.11.1
- Gradle: 8.12 → 8.14
- Kotlin: 2.1.0 → 2.2.20

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pubspec.yaml

@@ -22,7 +22,7 @@ dependencies:
   flutter_local_notifications: ^17.2.2
   url_launcher: ^6.3.0
   flutter_linkify: ^6.0.0
-  app_links: ^6.1.4
+  app_links: ^7.0.0
 
   # Auth, storage, prefs
   oauth2_client: ^4.2.0
@@ -35,7 +35,7 @@ dependencies:
   path: ^1.8.3
   path_provider: ^2.1.0
   uuid: ^4.0.0
-  package_info_plus: ^8.0.0
+  package_info_plus: ^9.0.0
   csv: ^6.0.0
   collection: ^1.18.0