Integration between get_steady_states and quantum cumulants

It would be cool to produce the linear response heatmaps, such as the ones found in https://quantumengineeredsystems.github.io/HarmonicBalance.jl/stable/tutorials/linear_response , for the steady states of the mean field equations found via QuantumCumulants.jl.

I guess the graph won't be for the operator but for its expectation value.