[BUG]: If indicies of scipy.csc_matrix are not sorted conversion to Eigen::SparseMatrix Fails in debug mode.

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What version (or hash if on master) of pybind11 are you using?

2.13.6

Problem description

scipy sparse matrix could have unsorted indicies. Conversion to Eigen type leads assertion:
eigen_assert( (m_outerIndex[outer+1]-m_outerIndex[outer]==0 || m_data.index(m_data.size()-1)<inner) && "Invalid ordered insertion (invalid inner index)");
However, if you call sort_indicies() before cast conversion would be correct.

Reproducible example code

Is this a regression? Put the last known working version here if it is.

Not a regression

Start by tracing pybind11's scipy.csc_matrix to Eigen::SparseMatrix conversion and compare behavior with the reported sort_indices() workaround. Reproduce the debug assertion using an unsorted sparse matrix; done means conversion succeeds and preserves the correct sparse values and indices.