Improvement: Mesh handle tutorials

[Vyp3er]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.28%. Comparing base (66cd94f) to head (ca472bd).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2348   +/-   ##
=======================================
  Coverage   82.28%   82.28%           
=======================================
  Files         125      125           
  Lines       20701    20701           
=======================================
  Hits        17033    17033           
  Misses       3668     3668           

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[lenaploetzke]

Partial review. Thank you for your work, this is really nice and my comments are mainly documentation! :)

[lenaploetzke]

We should rename this as we try to hide the "forest". Do you have an idea? Also maybe we should write a Readme such that it is clear why this is "step3" although we have no step 1 and 2 in this folder. I removed the "step5" for the other mesh handle tutorial but maybe its good to keep the name but state it clearly in the readme (and link to steps 0-2 there as they are necessary to understand also for the mesh handle)

[lenaploetzke]

I prefer t8_3D_vec here (which is essentially the same but clearer)

[lenaploetzke]

We should also think of something different than "tutorial" here. Any ideas?

[lenaploetzke]

We should also add a step here such that the files are not overridden by the next step. Maybe we can do step_mh3 or smth like this? (for mesh handle). Maybe you have a better idea, i am not fully convinced of my idea.