Feature: Add functionality to mesh handle

[lenaploetzke]

Closes #2085

Describe your changes here:
This PR adds multiple functions to the element of a mesh handle, e.g. the diameter and face related functionality as the area of a specific face. We have caches for new functions and new functionality is tested.
Moreover the code is largely restructured to make it shorter and important functions in the element are more visible now.
The testing strategy is sharpened.

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General

• The reviewer executed the new code features at least once and checked the results manually.
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Tests

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License

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 77.66%. Comparing base (f148d49) to head (9eea4ff).

Additional details and impacted files

@@                        Coverage Diff                         @@
##           handle-add-constructor-wrapper    #2084      +/-   ##
==================================================================
+ Coverage                           77.29%   77.66%   +0.37%     
==================================================================
  Files                                 113      113              
  Lines                               19047    19127      +80     
==================================================================
+ Hits                                14722    14855     +133     
+ Misses                               4325     4272      -53     

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