Add 3D multi-ion GLM-MHD equations for the TreeMesh solver

[amrueda]

This PR introduces the 3D multi-ion GLM-MHD equations. The implementation closely follows the 2D implementation (#2196), with the main difference being the inclusion of fluxes, non-conservative terms, and wave speeds for orientation == 3.

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 99.65217% with 2 lines in your changes missing coverage. Please review.

Project coverage is 96.42%. Comparing base (bde0afc) to head (0d72a48).

Files with missing lines	Patch %	Lines
src/equations/ideal_glm_mhd_multiion_3d.jl	99.65%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2215      +/-   ##
==========================================
+ Coverage   96.37%   96.42%   +0.05%     
==========================================
  Files         486      487       +1     
  Lines       39186    39761     +575     
==========================================
+ Hits        37764    38337     +573     
- Misses       1422     1424       +2     

Flag	Coverage Δ
unittests	96.42% <99.65%> (+0.05%)	⬆️

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