Style methods/attributes of UML class individually

[kusnezoff-alexander]

I would like to highlight certain methods in my d2 UML Diagram like for example:

Square: {
    shape: class

    +side: int

    +Area(): int {
      style: {
        fill: "#E0F7FA"
      }
   }
    +Perimeter(): int
}

to change the color and make the highlighted text bold/italic. Adding such more fine-grained styling options would be nice

Might be related to #2699