move motile-toolbox code to funtracks

[AnniekStok]

Copy motile toolbox code to funtracks. I have done little more than copying the code, ensuring we use the same NodeAttr/EdgeAttr references (though to be deprecated), making sure the tests pass, and making ruff happy. Do we want to do any other reorganization here?

[codecov]

Codecov Report

❌ Patch coverage is 96.37306% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 90.69%. Comparing base (d0745b8) to head (cec43f3).
⚠️ Report is 12 commits behind head on main.

Files with missing lines	Patch %	Lines
src/funtracks/utils/_segmentation_utils.py	87.87%	4 Missing ⚠️
src/funtracks/candidate_graph/iou.py	94.64%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #140      +/-   ##
==========================================
+ Coverage   90.20%   90.69%   +0.48%     
==========================================
  Files          52       57       +5     
  Lines        2654     2847     +193     
==========================================
+ Hits         2394     2582     +188     
- Misses        260      265       +5     

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[cmalinmayor]

👍 🐯

[cmalinmayor]

Move over tests for these functions from the toolbox :)

[cmalinmayor]

🎉