addSignature(contract, sender, nftIdx, currency)

Feature	Returns raw operation to sign NFT as creator.
Parameters	string contract address, string creator address, string | int nftIdx, string currencyID
Return Value	object sign operation

example

const contractAddress = "0x07469989b2562afF5E5C3B116CD3AA5Ef814e5a1fca";
const creator = "0x4874C17C354c498cf44D2946612DBe47fBcE7E87fca";
const nftIdx = 0;
const currencyID = "MCC";

const rawOperation = mitum.nft.sign(contractAddress, creator, nftID, currencyID);
console.log(rawOperation);

// output
Operation {
  id: 'mitum',
  fact: AddSignatureFact {
    hint: Hint { s: 'mitum-nft-add-signature-operation-fact' },
    token: Token { s: '2024-06-25 06:31:34.448 +0000 UTC' },
    _hash: <Buffer 11 c9 c8 fc 96 09 5d ab f0 19 81 59 96 24 da ca e1 b6 f5 47 c9 49 e9 f3 63 66 e3 45 90 8f 3b d2>,
    sender: Address {
      s: '0x4874C17C354c498cf44D2946612DBe47fBcE7E87fca',
      type: 'mitum'
    },
    items: [ [AddSignatureItem] ]
  },
  hint: Hint { s: 'mitum-nft-add-signature-operation' },
  _factSigns: [],
  _hash: <Buffer >
}