Function recover_secret_pruned2 

pub fn recover_secret_pruned2(
    e0: &Curve2,
    basis_a: (&Point2, &Point2),
    ell: u64,
    a: u32,
    basis_b: (&Point2, &Point2),
    images: (&Point2, &Point2),
    target: &Curve2,
) -> Option<(BigInt, Point2, usize)>

Oracle-pruned images → generator recovery. Walks the ℓ-adic keyspace tree but consults the isogeny graph reachability oracle (backward BFS from the public codomain target) at every node, pruning any branch that can no longer reach the target. Returns the secret, its generator, and the number of leaf image-tests performed (the pruned search visits only the target’s Aut-orbit). Same answer as recover_secret2 — soundness guarantees the true path is never pruned.