Move Jacobian for para P4est to respective files, add muladd

[DanielDoehring]

The wrong "place" of apply_jacobian_parabolic! happened in the bug-fixing PR https://github.com/trixi-framework/Trixi.jl/pull/1668/files .

The @muladd macro was missing actually all the time,w as this intended @jlchan ?

Edit: Most of the changes are actually due to the formatter

---

@jlchan There are actually multiple files within src/solvers/dgmulit which lack (?) the @muladd macro.

[github-actions]

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[codecov]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (dfd632e) 94.98% compared to head (f006d33) 96.38%.

Files	Patch %	Lines
src/solvers/dgsem_p4est/dg_2d_parabolic.jl	97.56%	1 Missing ⚠️
src/solvers/dgsem_p4est/dg_3d_parabolic.jl	97.14%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1807      +/-   ##
==========================================
+ Coverage   94.98%   96.38%   +1.40%     
==========================================
  Files         455      455              
  Lines       36391    36391              
==========================================
+ Hits        34564    35074     +510     
+ Misses       1827     1317     -510     

Flag	Coverage Δ
unittests	96.38% <97.37%> (+1.40%)	⬆️

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[DanielDoehring]

The check fails due to addition of the @muladd macro, compare

https://github.com/trixi-framework/Trixi.jl/actions/runs/7571256532/job/20618434805?pr=1807#step:7:7060

to

https://github.com/trixi-framework/Trixi.jl/actions/runs/7580977356/job/20647716452?pr=1781#step:7:7064

[jlchan]

Sorry - I missed this. Will review later today

[jlchan]

Thanks for reorganizing things and adding @muladd! I didn't intend to leave @muladd off, I just forgot.

I think @muladd is not included for several DGMulti files because it would interfered with Revise.jl and broke recompilation. This happened when @muladd was wrapping complex type aliases, if I remember correctly.

[DanielDoehring]

Sorry - I missed this. Will review later today

No worries, this did not slow down any of my other plans!