This is a medium-term issue that we should start considering to do since PyBaMM will migrate to using the IDAKLU solver as the default instead of the CasadiSolver.

This requires fixing the sdist, compiling SuiteSparse, and compiling SUNDIALS with KLU linked from SuiteSparse. We might need to patch PyBaMM to not use the CasADi Python package and compile the C interface ourselves (with minimal interfaces), and later turn binary relocation on for the feedstock. We could also introduce additional extension modules for this task.

We can then remove it and package pybammsolvers as a separate conda-forge feedstock to use here as a dependency once i. pybamm-team/PyBaMM#4487 is done and ii. things are stable enough for at least one release after the transition