Collect longitudinal FreeSurfer derivatives when available

[tsalo]

What would you like to see added in this software?

As far as I can tell, now that nipreps/smriprep#480 has been merged, sMRIPrep can collect session-wise FreeSurfer derivatives (freesurfer/<subject_id>_<session_id>), but it doesn't collect longitudinal pipeline derivatives when available (freesurfer/<subject_id>_<session_id>.long.<subject_id>). It seems like something we could support by updating niworkflows.interfaces.patches.FreeSurferSource to use the longitudinal folder when it exists.

Do you have any interest in helping implement the feature?

Yes

Additional information / screenshots

No response

[effigies]

Sure, if you understand how that works, I'm happy to work with longitudinal directories.