message: test: add broadcast tests
diff: @@ -1518,6 +1518,50 @@ test('Transaction broadcast success', async () => {
  expect(response as TxBroadcastResultOk).toEqual({ txid: 'success' });
  });
  +test('Transaction broadcast success with string network name', async () => {
  + const transaction = await makeSTXTokenTransfer({
  + recipient: standardPrincipalCV('SP3FGQ8Z7JY9BWYZ5WM53E0M9NK7WHJF0691NZ159'),
  + amount: 12345,
  + senderKey: "edf9aee84d9b7abc145504dde6726c64f369d37ee34ded868fabd876c26570bc01",
  + network: 'mainnet',
  + fee: 0,
  + nonce: 0,
  + memo: "test memo",
  + anchorMode: AnchorMode.Any
  + });
  +
  + fetchMock.mockOnce('success');
  +
  + const response: TxBroadcastResult = await broadcastTransaction(transaction, 'mainnet');
  +
  + expect(fetchMock.mock.calls.length).toEqual(1);
  + expect(fetchMock.mock.calls[0][0]).toEqual(new StacksMainnet().getBroadcastApiUrl());
  + expect(fetchMock.mock.calls[0][1]?.body).toEqual(transaction.serialize());
  + expect(response as TxBroadcastResultOk).toEqual({ txid: 'success' });
  +});
  +
  +test('Transaction broadcast success with network detection', async () => {
  + const transaction = await makeSTXTokenTransfer({
  + recipient: standardPrincipalCV('SP3FGQ8Z7JY9BWYZ5WM53E0M9NK7WHJF0691NZ159'),
  + amount: 12345,
  + senderKey: "edf9aee84d9b7abc145504dde6726c64f369d37ee34ded868fabd876c26570bc01",
  + network: 'testnet',
  + fee: 0,
  + nonce: 0,
  + memo: "test memo",
  + anchorMode: AnchorMode.Any
  + });
  +
  + fetchMock.mockOnce('success');
  +
  + const response: TxBroadcastResult = await broadcastTransaction(transaction);
  +
  + expect(fetchMock.mock.calls.length).toEqual(1);
  + expect(fetchMock.mock.calls[0][0]).toEqual(new StacksTestnet().getBroadcastApiUrl());
  + expect(fetchMock.mock.calls[0][1]?.body).toEqual(transaction.serialize());
  + expect(response as TxBroadcastResultOk).toEqual({ txid: 'success' });
  +});
  +
  test('Transaction broadcast with attachment', async () => {
  const recipient = standardPrincipalCV('SP3FGQ8Z7JY9BWYZ5WM53E0M9NK7WHJF0691NZ159');
  const amount = 12345;
  