Support for 3d idp mortars on TreeMesh

[bennibolm]

This PR also contains the implementation of subcell 3D from bennibolm#143 and 2D idp mortars from #2305.

[github-actions]

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Created with ❤️ by the Trixi.jl community.

[codecov]

Codecov Report

❌ Patch coverage is 70.23861% with 686 lines in your changes missing coverage. Please review.
✅ Project coverage is 95.36%. Comparing base (6900d5a) to head (4f49c88).

Files with missing lines	Patch %	Lines
src/solvers/dgsem_tree/dg_3d_subcell_limiters.jl	41.70%	337 Missing ⚠️
src/solvers/dgsem_p4est/dg_3d_subcell_limiters.jl	57.71%	225 Missing ⚠️
src/equations/ideal_glm_mhd_3d.jl	42.42%	57 Missing ⚠️
src/solvers/dgsem_tree/containers_3d.jl	69.08%	47 Missing ⚠️
src/solvers/dgsem_p4est/subcell_limiters_3d.jl	97.64%	8 Missing ⚠️
src/solvers/dgsem_tree/subcell_limiters_3d.jl	98.27%	6 Missing ⚠️
src/callbacks_stage/subcell_bounds_check_3d.jl	93.65%	4 Missing ⚠️
...llbacks_stage/subcell_limiter_idp_correction_3d.jl	98.02%	2 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff               @@
##           bb/idp-amr    #2626      +/-   ##
==============================================
- Coverage       96.68%   95.36%   -1.32%     
==============================================
  Files             540      550      +10     
  Lines           44031    46335    +2304     
==============================================
+ Hits            42568    44186    +1618     
- Misses           1463     2149     +686     

Flag	Coverage Δ
unittests	95.36% <70.24%> (-1.32%)	⬇️

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