Bug: `arena_matrix` traits aren't specialized properly for sparse matrices

Description

This is one of those things where I can't tell if it's a bug or a user error, but I'm trying to use an arena_matrix<Eigen::SparseMatrix<double>> type and I'm getting an error related to the setting of the internal Eigen traits. In particular, I'm getting

/home/dan-simpson/Documents/math/stan/math/rev/core/arena_matrix.hpp:490:38: error: ‘PlainObjectTypeInnerSize’ is not a member of ‘Eigen::internal::traits<stan::math::arena_matrix<Eigen::SparseMatrix<double> > >::base’ {aka ‘Eigen::internal::traits<Eigen::Map<Eigen::SparseMatrix<double>, 0, Eigen::Stride<0, 0> > >’}
  490 |     PlainObjectTypeInnerSize = base::PlainObjectTypeInnerSize,
      |                                      ^~~~~~~~~~~~~~~~~~~~~~~~
/home/dan-simpson/Documents/math/stan/math/rev/core/arena_matrix.hpp:491:38: error: ‘InnerStrideAtCompileTime’ is not a member of ‘Eigen::internal::traits<stan::math::arena_matrix<Eigen::SparseMatrix<double> > >::base’ {aka ‘Eigen::internal::traits<Eigen::Map<Eigen::SparseMatrix<double>, 0, Eigen::Stride<0, 0> > >’}
  491 |     InnerStrideAtCompileTime = base::InnerStrideAtCompileTime,
      |                                      ^~~~~~~~~~~~~~~~~~~~~~~~
/home/dan-simpson/Documents/math/stan/math/rev/core/arena_matrix.hpp:492:38: error: ‘OuterStrideAtCompileTime’ is not a member of ‘Eigen::internal::traits<stan::math::arena_matrix<Eigen::SparseMatrix<double> > >::base’ {aka ‘Eigen::internal::traits<Eigen::Map<Eigen::SparseMatrix<double>, 0, Eigen::Stride<0, 0> > >’}
  492 |     OuterStrideAtCompileTime = base::OuterStrideAtCompileTime,
      |                                      ^~~~~~~~~~~~~~~~~~~~~~~~
/home/dan-simpson/Documents/math/stan/math/rev/core/arena_matrix.hpp:493:23: error: ‘Alignment’ is not a member of ‘Eigen::internal::traits<stan::math::arena_matrix<Eigen::SparseMatrix<double> > >::base’ {aka ‘Eigen::internal::traits<Eigen::Map<Eigen::SparseMatrix<double>, 0, Eigen::Stride<0, 0> > >’}
  493 |     Alignment = base::Alignment,

I strongly suspect this is because the traits defined in SpraseCore/SparseMap.h don't line up with those in Core/Map.h, so the template defining them for arena_matrix needs to be specialized.

Start in stan/math/rev/core/arena_matrix.hpp around the arena_matrix traits definition at line 483, then compare the trait definitions in lib/eigen_3.4.0/Eigen/src/SparseCore/SparseMap.h and Core/Map.h. Reproduce the reported arena_matrix<Eigen::SparseMatrix> compilation error and determine which sparse traits are missing or incompatible. Done means the sparse arena_matrix type compiles without the reported trait errors.