tapTweak.js

const internal_priv = ECPair.fromPrivateKey(
    Buffer.from(
        "1229101a0fcf2104e8808dab35661134aa5903867d44deb73ce1c7e4eb925be8",
        "hex",
    ),
);
const pub_key = toXOnly(internal_priv.publicKey);

const coldReserveScriptText1 = `${bitcoin.script.number
    .encode(144)
    .toString("hex")} OP_CHECKSEQUENCEVERIFY OP_DROP 9997a497d964fc1a62885b05a51166a65a90df00492c8d7cf61d6accf54803be OP_CHECKSIG`;
const coldReserveScript1 = bitcoin.script.fromASM(coldReserveScriptText1);
const coldReserveScriptText2 = `OP_SHA256 6c60f404f8167a38fc70eaf8aa17ac351023bef86bcb9d1086a19afe95bd5333 OP_EQUALVERIFY 4edfcf9dfe6c0b5c83d1ab3f78d1b39a46ebac6798e08e19761f5ed89ec83c10 OP_CHECKSIG`;
const coldReserveScript2 = bitcoin.script.fromASM(coldReserveScriptText2);

const coldReserveScriptTree = [
    {
        output: coldReserveScript1,
    },
    {
        output: coldReserveScript2,
    },
];
const {
    address: _coldReserveAddress,
    pubkey: _coldReservePubkey,
    hash: _coldReserveHash,
} = bitcoin.payments.p2tr({
    internalPubkey: pub_key,
    scriptTree: coldReserveScriptTree,
});

let tapTweak = `0x${_coldReserveHash.toString("hex")}`;
console.log(tapTweak);