Diffusive CFL P4est

[DanielDoehring]

Adds diffusive CFL routines for P4estMesh

[github-actions]

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[codecov]

Codecov Report

❌ Patch coverage is 96.49123% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 96.84%. Comparing base (8bd7b7b) to head (3058001).

Files with missing lines	Patch %	Lines
src/callbacks_step/stepsize_dg2d.jl	94.59%	2 Missing ⚠️
src/callbacks_step/stepsize_dg3d.jl	95.83%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2696      +/-   ##
==========================================
- Coverage   96.84%   96.84%   -0.00%     
==========================================
  Files         549      550       +1     
  Lines       43329    43427      +98     
==========================================
+ Hits        41960    42054      +94     
- Misses       1369     1373       +4     

Flag	Coverage Δ
unittests	96.84% <96.49%> (-<0.01%)	⬇️

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[jlchan]

Nice, thanks for adding this. I'll try to take a look later tonight

[jlchan]

Overall looks good, just requested some slightly expanded comments on the mapping to the reference element.

[jlchan]

Thanks!

[DanielDoehring]

I shortened one of the 3D tests