WIP: Unify create_cache for ControllerThreeLevel* and the different mesh types

[amrueda]

No description provided.

[github-actions]

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[JoshuaLampert]

Would it make sense to put this method in amr_dg.jl instead since it is not dimension-dependent anymore?

[JoshuaLampert]

Or probably even in amr.jl?

[sloede]

Do we have amr_dg.jl as a file? Since it references the DG solver, that would be my pick

[JoshuaLampert]

Yes

[ranocha]

@sloede Does moving this stuff violate your "better be explicit and duplicate code for several space dimensions" policy?

[sloede]

I believe there is precedence where we have replaced literally-identical implementations with a single function (e.g., solver functions for the different mesh types). So yes, I'd be ok with that :-)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.27%. Comparing base (1e1f643) to head (d3bc89f).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2285      +/-   ##
==========================================
+ Coverage   89.49%   96.27%   +6.78%     
==========================================
  Files         490      490              
  Lines       39507    39498       -9     
==========================================
+ Hits        35355    38025    +2670     
+ Misses       4152     1473    -2679     

Flag	Coverage Δ
unittests	96.27% <100.00%> (+6.78%)	⬆️

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