✨ add script to extract surfaces from labels

[dyollb]

What do these changes do?

This PR adds functionality to produce surfaces from 3d labels:

• [x] the script saves the surfaces as .ply files, for the selected tissues
• [x] the name is taken from the tissue list file/dict
• [ ] create little helper function to render surfaces, or image slices with cut-surfaces like so

[codecov[bot]]

Codecov Report

Merging #44 (3deedaa) into main (d4a265e) will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##             main      #44   +/-   ##
=======================================
  Coverage   19.48%   19.48%           
=======================================
  Files          47       47           
  Lines        2392     2392           
  Branches      395      395           
=======================================
  Hits          466      466           
  Misses       1900     1900           
  Partials       26       26           

Flag	Coverage Δ
unittests	19.48% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update 6a7bfb7...3deedaa. Read the comment docs.