Create new method GET_ADAHANDLE

[mmahut]

Lace light wallet needs a way to resolve an adahandle, we need therefore implement a new method for doing this, where the handle itself will be passed in param.

The method is very easy, just take how the queries works from their official website.

const handleName = 'web3';
const policyID = 'f0ff48bbb7bbe9d59a40f1ce90e9e9d0ff5002ec48f232b49ca0fb9a';

// A blank Handle name should always be ignored.
if (handleName.length === 0) {
  // Handle error.
}

// Convert handleName to hex encoding.
const assetName = Buffer.from(handleName).toString('hex');

// Fetch matching address for the asset.
const data = await fetch(
  `https://cardano-mainnet.blockfrost.io/api/v0/assets/${policyID}${assetName}/addresses`,
  {
    headers: {
      // Your Blockfrost API key
      project_id: process.env.BLOCKFROST_API_KEY,
      'Content-Type': 'application/json'
    }
  }
).then(res => res.json());

if (data?.error) {
  // Handle error.
}

const [{ address }] = data;
console.log(address); // addr1qx3c9...