[ENH] Add option to choose default surfacevisualization style for nilearn.plotting.view_img_on_surf

[JohannesWiesner]

Is there an existing issue for this?

• [x] I have searched the existing issues

Describe your proposed enhancement in detail.

Currently, the surface by default will be displayed as inflated. the pial view is only accessible by post-hoc clicking on the button on the bottom left. Could this be directly set when calling the function?

Benefits to the change

I call this function using a for-loop for multiple ROI sets. Right now it's a little tedious to toggle this view n-times using the GUI

Pseudocode for the new behavior, if applicable

# insert your code below

[Remi-Gau]

that's fine with me: wanna try to open a pull request for it?