Function execute_steps_with 

pub fn execute_steps_with(
    ctx: &Ctx<'_>,
    steps: Vec<Step>,
    checks: Option<&Assert>,
) -> Result<AssertResult>

Execute steps with an explicit Assert for worker checks. When checks is Some, it overrides ctx.assert. When None, uses ctx.assert (the merged three-layer config).

Thin wrapper around execute_scenario_with with an empty Backdrop — every Step’s effects (cgroups, workloads, payloads) tear down at the step boundary.