WIP: Sc/Enhanced p4est mesh views

[SimonCan]

Enhance p4est mesh views. Allows for a cell-selection for each view.

[github-actions]

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Code quality

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Testing

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Created with ❤️ by the Trixi.jl community.

[codecov]

Codecov Report

Attention: Patch coverage is 65.51724% with 40 lines in your changes missing coverage. Please review.

Project coverage is 77.55%. Comparing base (f9f1a74) to head (72a85fd).

Files with missing lines	Patch %	Lines
src/meshes/p4est_mesh_view.jl	64.29%	30 Missing ⚠️
src/meshes/mesh_io.jl	16.67%	10 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (f9f1a74) and HEAD (72a85fd). Click for more details.

HEAD has 3 uploads less than BASE

Flag	BASE (f9f1a74)	HEAD (72a85fd)
unittests	25	22

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #2110       +/-   ##
===========================================
- Coverage   96.42%   77.55%   -18.87%     
===========================================
  Files         489      490        +1     
  Lines       39376    39425       +49     
===========================================
- Hits        37966    30574     -7392     
- Misses       1410     8851     +7441     

Flag	Coverage Δ
unittests	77.55% <65.52%> (-18.87%)	⬇️

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