Function try_kernel 

pub fn try_kernel(
    gpu: &dyn GpuBackend,
    module: &str,
    func: &str,
) -> KernelHandle

2026-09-25: Look up module::func, returning KernelHandle(0) (and a debug log) when the lookup fails. A zero handle is a slower path or a missing feature, so a caller must check it before launching.

#[track_caller] here and on GpuBackend::kernel makes the audit record the caller’s file:line rather than this function’s.