The proof master key is needed to check the delegation and the signature included in the `AvaHello` message. The `LimitedProofId` is required to check that the provided proof master key actually belongs to the advertised proof, by allowing to compute the proofid using the limited id and master key, and then comparing the computed id to the one included in the delegation.
The delegation verification no longers needs to be done in `PeerManager::addNode`, as the node is banned if the delegation verification fails on avahello reception.