[ENH]: Support for parcellations from siibra

[synchon]

Are you requiring a new dataset or marker?

• I understand this is not a marker or dataset request

Which feature do you want to include?

Adding siibra will let us provide users with access to the parcellations that it provides. As its API is still in development, care should be taken before integrating.

How do you imagine this integrated in junifer?

As other in-built parcellation with some tricks ;)

Do you have a sample code that implements this outside of junifer?

No response

Anything else to say?

No response