Function bind_check 

pub fn bind_check(
    selector: String,
    verified_at_sha: String,
    platforms: Vec<String>,
    triggered_by: Vec<String>,
    surfaces: Vec<String>,
) -> Result<Check, String>

The --bind-check harvest: build a harvested Check::Test (counter_test None, full liveness) for the given selector, reusing the Task-5 migrate-only constructor. This is the SAME constructor the harvested-binding path uses — no second half-harvest gate. The caller attaches it to a ground.