Direct editing of JSON files would be very helpful

[tyronx]

The most straightforward process for me would be:

1. Double click on a .json under windows opens the model creator
2. I do my changes and press CTRL + S and the programm saves the model under the same name
3. I do a slightly different model and select "Save as" in the File menu to create a new model

Until there is undo functionality, a "Do you really..." popup could show everytime you want to save an existing file.