WIP: Sc/p4est view coupled hanging nodes

[SimonCan]

Added capability of coupling pest mesh views with hanging/non-conforming nodes.

[github-actions]

Review checklist

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[github-actions]

[JuliaFormatter] _{reported by reviewdog 🐶}

Suggested change

	x1, x2 = x
	v1 = 0.0
	v2 = 0.0
	b = 0.0
	H = 1.0
	return prim2cons(SVector(H, v1, v2, b), equations)
	x1, x2 = x
	v1 = 0.0
	v2 = 0.0
	b = 0.0
	H = 1.0
	return prim2cons(SVector(H, v1, v2, b), equations)

[github-actions]

[JuliaFormatter] _{reported by reviewdog 🐶}

Suggested change

[codecov]

Codecov Report

❌ Patch coverage is 4.91453% with 445 lines in your changes missing coverage. Please review.
✅ Project coverage is 94.54%. Comparing base (d52e08d) to head (2b94b79).

Files with missing lines	Patch %	Lines
...discretization/semidiscretization_coupled_p4est.jl	0.00%	211 Missing ⚠️
src/meshes/p4est_mesh_view.jl	0.00%	88 Missing ⚠️
src/solvers/dgsem_p4est/dg_2d.jl	0.00%	60 Missing ⚠️
src/solvers/dgsem_tree/dg_2d.jl	26.32%	28 Missing ⚠️
...xamples/p4est_2d_dgsem/elixir_euler_mhd_coupled.jl	0.00%	21 Missing ⚠️
src/solvers/dgsem_unstructured/dg_2d.jl	0.00%	14 Missing ⚠️
...emidiscretization/semidiscretization_hyperbolic.jl	0.00%	9 Missing ⚠️
examples/structured_2d_dgsem/test.jl	0.00%	7 Missing ⚠️
...xamples/p4est_2d_dgsem/elixir_advection_coupled.jl	0.00%	5 Missing ⚠️
src/solvers/dgsem_p4est/dg.jl	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2598      +/-   ##
==========================================
- Coverage   96.81%   94.54%   -2.27%     
==========================================
  Files         533      537       +4     
  Lines       42804    43247     +443     
==========================================
- Hits        41438    40887     -551     
- Misses       1366     2360     +994     

Flag	Coverage Δ
unittests	94.54% <4.91%> (-2.27%)	⬇️

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