Constant BINDING_SIG_LEN 

pub const BINDING_SIG_LEN: usize = 65;

Exact byte length of a BindNodeId client-binding signature (r‖s‖v, 32+32+1). The same EOA off-chain EIP-712 signing form as SLASH_SIG_LEN / VOUCHER_SIG_LEN (ADR 024 §Off-Chain Signature Verification — EOA Recovery Only); pinned by ClientBinding::validate.