Branch changes

By default Xcode suggests the Branch Changes condition that starts a new build
for every change to your Git repository’s default branch.

For your app’s iOS variant, it’s reasonable that you would want Xcode Cloud to
trigger your workflow after you’ve made changes to your flutter packages, or
modified either the Dart or iOS source files within the lib\ and ios\
directories.

This can be achieved by using the following Files and Folders conditions:

Next build number

Xcode Cloud defaults the build number for new workflows to 1 and increments
it per successful build. If you’re using an existing app with a higher build
number, you’ll need to configure Xcode Cloud to use the correct build number
for it’s builds by simply specifying the Next Build Number in your iteration.

Check out Setting the next build number for Xcode Cloud builds for more
information.