Add QubitSparsePauliList.commutes

[joshuasn]

Summary

This PR adds QubitSparsePauliList.commutes that computes the commutation relations of the given sparse Pauli list with another, returning a (num_self_paulis, num_other_paulis) array of bools.

Details and comments

Useful for certain Pauli channel computations rather with a modest speedup over iterating through the lists with QubitSparsePauli.commutes (from 578ms to 239ms on 729 terms).

AI/LLM disclosure

• I didn't use LLM tooling, or only used it privately.
• I used the following tool to help write this PR description:
• I used the following tool to generate or modify code:

[qiskit-bot]

One or more of the following people are relevant to this code:

• @Qiskit/terra-core

[coveralls]

Coverage Report for CI Build 25948312118

Coverage decreased (-0.008%) to 87.702%

Details

• Coverage decreased (-0.008%) from the base build.
• Patch coverage: 21 of 21 lines across 1 file are fully covered (100%).
• 15 coverage regressions across 3 files.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

15 previously-covered lines in 3 files lost coverage.

File	Lines Losing Coverage	Coverage
crates/circuit/src/parameter/symbol_expr.rs	9	73.88%
crates/qasm2/src/lex.rs	5	92.29%
crates/transpiler/src/passes/unitary_synthesis/decomposers.rs	1	94.71%

---

Coverage Stats

Relevant Lines:	123051
Covered Lines:	107918
Line Coverage:	87.7%
Coverage Strength:	954192.31 hits per line

---

💛 - Coveralls