Major rework of GRHD project to include new broadcasting interface.
The goal is to get a TOV evolution with the AV method.
PR contains various refactors:
initialdata/: We promote this to a separate env in order to add CairoMakie for plotting.
refactored and improve initialdata/SphericalAccretion.jl solver so that it agrees with various references: solver from bugner's thesis (extract from bamps), plots from two papers from Papadoulos.
refactored initialdata/TOV.jl to not depend on dg1d.jl anymore, instead use OrindaryDiffEq and CairoMakie for plots
copy of cons2prim from SRHD. these two versions should be merged eventually, but will do in a separate PR
implement spherical1d formulation: this is a rewrite of the evolution GRHD equations to work with non-zero radial shift vector. this is needed to evolve the spherical accretion test in cowling approximation where there should be no dynamics.
implement rescaled_spherical1d formulation: this is a rewrite of the previous formulation based on the generalized Valencia formulation (cf. Montero, Baumgarte paper from 2017); the auxiliary metric is chosen such that coordinate singularities at r=0 in the source terms are cancelled; doesn't work atm
allow the spherical1d to include r=0 in the domain by using symmetry conditions to evaluate source terms at r=0 (workaround for rescaled_spherical1d not working right now)
new ref tests: bondi accretion and TOV star
implement a differentiate! method on Mesh in order to compute derivatives by hand, if needed
