Add Sort by Label option to the annotations side bar

[genaroNF]

Motivation and context

The issue 9531 proposed the creation of a new sort option that allows users to sort by label. Since it seems pretty straightforward and useful, I decided to give it a go

Closes: #9531

How has this been tested?

To test this, I created a project with multiple labels, then added an image, and I annotated multiple bounding boxes for the different labels. After that, I selected the option and confirmed it was working.

Computer.Vision.Annotation.Tool.-.Brave.2025-08-19.19-33-04.mp4

After it, I added an e2e test, which can be reviewed in this PR

Checklist

• I submit my changes into the develop branch
• I have created a changelog fragment
• [ ] I have updated the documentation accordingly
• I have added tests to cover my changes
• I have linked related issues (see GitHub docs)

License

• I submit my code changes under the same MIT License that covers the project.
  Feel free to contact the maintainers if that's a concern.

[sonarqubecloud]

Quality Gate failed

Failed conditions
1 Security Hotspot

See analysis details on SonarQube Cloud

[genaroNF]

Quality Gate failed

Failed conditions 1 Security Hotspot

See analysis details on SonarQube Cloud

Not sure what can I do with this, it was already part of the test