Image cropper config improvements

[JesmoDev]

Autofills the alias in the image cropper config. Focuses the label input after adding a crop

Fixes umbraco/Umbraco-CMS#16159 Fixes umbraco/Umbraco-CMS#16160

Description

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [ ] Chore (minor updates related to the tooling or maintenance of the repository, does not impact compiled assets)

Checklist

• [x] If my change requires a change to the documentation, I have updated the documentation in this pull request.
• [x] I have read the CONTRIBUTING document.
• [x] I have added tests to cover my changes.