// Define the runestone with the burn flag set to true and amount to 100,000
let runestone = monkeymilkmoneyhoney {
    burn: true,
    amount: 100000,
    ..Default::default()
};

// Encipher the runestone to get the script public key
let script_pubkey = runestone.encipher();

// Ensure the script public key length is within the maximum OP_RETURN size
ensure!(
    script_pubkey.len() <= 82,
    "runestone greater than maximum OP_RETURN size: {} > 82",
    script_pubkey.len()
);

// Create an unfunded transaction with the specified inputs and outputs
let unfunded_transaction = Transaction {
    version: 2,
    lock_time: LockTime::ZERO,
    input: vec![
        tx_input_to_spend,
    ],
    output: vec![
        TxOut {
            script_pubkey,
            value: 0,
        },
    ],
};

// The remaining logic is the same as before