Add SKQD tutorial

[kevinsung]

Fixes #3003

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[nathanearnestnoble]

@miamico

[nathanearnestnoble]

Thanks Kevin! I think it is fairly solid, some minor feedback:

• I think it would be useful to reference our Krylov tutorial as well, in case people want to gain a deeper understand of the specifics around it
• @miamico made a good point that I wanted to raise: As you are specifically using the impurity anderson hamiltonian from the paper, you need to introduce an additional step of changing from position basis to momentum basis. I think there could be a benefit to have two component to the tutorial: a simpler hamitlonian that does not require this mapping because it is already sparse, and then a second "more advanced" part II highlight the specific step of basis change to overcome the issue of having a non-sparse matrix and is brief on other elements of the workflow already discussed.

[kevinsung]

@kevinsung Thanks! I left some comments via the ReviewNB app here.

@jenglick I just updated the PR to use the new diagonalize_fermionic_hamiltonian funtion and then went to revisit your comments, but this is what I see when I click the link:

[miamico]

This looks great! Just a couple comments

• I think we should also refer to the KQD paper (and tutorial) as the convergence guarantee of the unitary krylov subspace are detailed there
• could you add a "Reference" section where the various sources (SQD, KQD, SKQD paper) are listed?

[kevinsung]

This looks great! Just a couple comments

* I think we should also refer to the [KQD paper ](https://arxiv.org/abs/2407.14431)(and [tutorial](https://quantum.cloud.ibm.com/docs/en/tutorials/krylov-quantum-diagonalization)) as the convergence guarantee of the unitary krylov subspace are detailed there

* could you add a "Reference" section where the various sources (SQD, KQD, SKQD paper) are listed?

Done