Fix normalization handling in MPS/MPO expectations - #1
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…leau - #1 pauli_combo_mpo windows to the operator support span (bond-1 identity outside [lo,hi]; operator factors I_outside (x) window-op). Callers unchanged; verified exact via to_dense. NB windowed gate_with_submpo_ is wrong here (fid 0.939) so we keep mpo.apply. - #2 _evolve_nu fuses apply+compress via mpo.apply(compress=True) (one sweep; max_bond=None exact stays lossless). - #3 STNState caches current_inverse_tableau, invalidated on apply_clifford/ do_tableau; tableau updates routed through STNState.do_tableau. Stress suite 17.4s -> 10.3s; 63 STN + 480 API/layout tests pass; n=10 depth-150 exact ~295ms, fidelity vs quimb = 1.0.
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This PR fixes normalization issues in tensor network expectation and sweep tracking paths, including avoiding double division for already-normalized MPS inputs and making sweep best-state tracking robust when state is unavailable.
expec_mposo MPS expectation values remain scale-invariant.tn_normwhile preserving stored exponent state.