[WIP] New matrix abstraction (SparseDifferentiation#87)

* start with permuted dense struct, without integration

* better polymorphism

* make hessian matrix

* dispatch for elementwise chainr rule hessian

* better polymorphism for copying sparsity pattern

* remove many to_csr

* remove memcpy in to_csr

* add profile for trimmed log reg

* infrastructure for matrix multiplication when one matrix is permuted_dense

* ran formatter

* better BTDA for permuted dense x permuted_dense

* more cache friendly BA_pd_csc_fill_values

* edits

* better permuted dense times CSC function

* better infrastructure permuted dense

* get rid of unnecessary allocation

* change name of some functions

* run formatter

* permutation dense preserving transpose implementation via index polymorhpim

* clean up multiply

* clean up matrix.h

* lazy allocation of dwork in permuted_dense

* Implement block_left_mult on permuted_dense

* swap dense matrix for permuted dense and delete dense_matrix

* more infrastructure

* better BA_pd_pd_fill_values

* add permuted dense polymorphism to left matmul

* minor

* add test

* clean up left_matmul and enable parameter

* fix filename

new convolve atom (SparseDifferentiation#85)

* initial iteration for convolve atom

* apply formatter

* adds test for row convolve in case it is 1d in python

* improve convention of data pointer when we have parameters for left and right matmul

* get rid of sparse matrix abstraction and just do CSR instead

* get rid of block abstraction and use non-block logic instead

* happy with convolve.c

---------

Co-authored-by: dance858 <danielcederberg1@gmail.com>

Change license header (SparseDifferentiation#81)

* update license header line for all source files

* add license to new files

* remove empty lines at the end of files

set version to 0.2.0 for release

update version

Add Gaussian cdf as atom (SparseDifferentiation#50)

* normal cdf

* broadcast bug fix

* run formatter

* update version

fix: install OpenBLAS in release CI for Ubuntu

The release workflow was missing the libopenblas-dev install step that
cmake.yml already has, causing BLAS-dependent builds to fail on Linux.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

COO support (SparseDifferentiation#47)

* basic coo support

* run formatter only on macos

* ran formatter

* added comment

* formatter

* updated version number

update version

updated version