What does this PR do?

This PR enhances the eval creation UI form by adding an interactive dropdown menu to the JsonPath field.
The dropdown menu gives users an easy way to see all of the availables paths on the object that will be parsed
when generating a prompt for the eval.

Type of change

• New feature (non-breaking change which adds functionality)

Mandatory Tasks

• Make sure you have self-reviewed the code. A decent size PR without self-review might be rejected.

Checklist

• I haven't read the contributing guide
• My code doesn't follow the style guidelines of this project (pnpm run format)
• I haven't commented my code, particularly in hard-to-understand areas
• I haven't checked if my PR needs changes to the documentation
• I haven't checked if my changes generate no new warnings (npm run lint)
• I haven't added tests that prove my fix is effective or that my feature works
• I haven't checked if new and existing unit tests pass locally with my changes