Change backend threading behavior

[afilogo]

This PR is based on the discussion #2159, having into account your feedback. I apologize for the late reply and hope did not make any mistake.

[github-actions[bot]]

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[DanielDoehring]

Thanks for your contribution! I am not so sure if we really want to offer other threading strategies (namely dynamic) in the main repository. Same holds also for the serial option - IMO, this is not really necessary, as one could just run the program with a single thread.

[afilogo]

Thanks for the feedback @DanielDoehring and @vchuravy. Appreciate you taking the time to review it. I thought it might increase user control, but I also understand your perspective.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 40.00000% with 6 lines in your changes missing coverage. Please review.

Project coverage is 96.79%. Comparing base (55d44d9) to head (657311f). Report is 41 commits behind head on main.

Files with missing lines	Patch %	Lines
src/auxiliary/math.jl	0.00%	6 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2417      +/-   ##
==========================================
- Coverage   96.80%   96.79%   -0.01%     
==========================================
  Files         495      495              
  Lines       40917    40919       +2     
==========================================
- Hits        39608    39607       -1     
- Misses       1309     1312       +3     

Flag	Coverage Δ
unittests	96.79% <40.00%> (-0.01%)	:arrow_down:

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[ranocha]

CI is failing, so it appears that something is off. Could you please take a look and see what's going on?

[afilogo]

CI is failing, so it appears that something is off. Could you please take a look and see what's going on?

I believe the issue is the in static macro "@static if _PREFERENCE_THREADING === :polyester && LoopVectorization.check_args(u_ode)" code line. It should be fine now.

[afilogo]

I've also missed a previous _PREFERENCE_POLYESTER line. Sorry about that.

[vchuravy]

@afilogo thank you very much for your contribution. I am going to bring this PR to the finish line in #2476