Function verify_csr_action 

pub fn verify_csr_action(
    matrix: &CsrMatrix,
    input: &[f64],
    device_ordinal: u16,
    policy: SparseActionPolicy,
    tolerance: SparseActionTolerance,
) -> Result<CudaCsrActionResult, Diagnostic>

Execute one finalized f64 CSR action on CUDA and compare it with the independent host operator under an explicit tolerance.

Errors

Returns a stable diagnostic for unavailable runtime/library/device, unsupported shape/index conversion, transfer or cuSPARSE failure, non-finite data, or disagreement with the host oracle.