Unify create_cache for ControllerThreeLevel* and the different mesh types

[amrueda]

The function create_cache was defined multiple times for ControllerThreeLevel and ControllerThreeLevelCombined, each using different mesh types of varying dimensions. However, all implementations performed the same task. Additionally, some combinations were missing (e.g., ControllerThreeLevelCombined with P4estMesh3D).

In this PR, I unify all create_cache functions for ControllerThreeLevel and ControllerThreeLevelCombined into a single implementation.

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.87%. Comparing base (567cf22) to head (f7055a4).
Report is 6 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2285      +/-   ##
==========================================
- Coverage   96.87%   96.87%   -0.00%     
==========================================
  Files         490      490              
  Lines       39512    39503       -9     
==========================================
- Hits        38275    38266       -9     
  Misses       1237     1237              

Flag	Coverage Δ
unittests	96.87% <100.00%> (-<0.01%)	⬇️

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[JoshuaLampert]

You said, we enable combinations, which were not supported before, such as ControllerThreeLevelCombined with P4estMesh3D. Could we add a test for that, e.g., by adding an elixir using this combination?