Tweak AVIF tuning and preferences

pubspec.yaml

@@ -173,10 +173,8 @@ flutter:
 
   # Enable generation of localization files
   generate: true
-  # To add assets to your application, add an assets section, like this:
-  # assets:
-  #   - images/a_dot_burr.jpeg
-  #   - images/a_dot_ham.jpeg
+  assets:
+    - screenshots/ios/
 
   # An image asset can refer to one or more resolution-specific "variants", see
   # https://flutter.dev/to/resolution-aware-images