text: Title: Support dark theme for JSONEditor
  Body: The `JSONEditor` does not look nice in dark theme:
  
  ![image](https://github.com/user-attachments/assets/02b638a4-238e-4c93-b550-970fba25f377)
  
  I can see that the js library can be dark styled:
  
  - https://github.com/josdejong/jsoneditor/blob/develop/examples/06_custom_styling.html
  - https://github.com/josdejong/jsoneditor/blob/develop/examples/css/darktheme.css