feat(wallet): pass isTestTransaction parameter to TSS transfer txrequests API

- Add isTestTransaction parameter to PrebuildTransactionOptions interface
- Pass isTestTransaction through prebuildTransactionTxRequests for transfer transactions
- Include isTestTransaction in PopulatedIntent and baseIntent objects
- Add unit test to verify isTestTransaction is properly passed through the call chain

This ensures the isTestTransaction flag is correctly sent to the
/api/v2/wallet/:walletId/txrequests endpoint for TSS wallets (e.g., NEAR)
when building transfer transactions.

TICKET: CS-6339

Author: sandra-wang-bitgo

modules/bitgo/test/v2/unit/wallet.ts

@@ -2362,6 +2362,49 @@ describe('V2 Wallet:', function () {
         });
       });
 
+      it('should build a transfer transaction with isTestTransaction flag', async function () {
+        const recipients = [
+          {
+            address: '6DadkZcx9JZgeQUDbHh12cmqCpaqehmVxv6sGy49jrah',
+            amount: '1000',
+          },
+        ];
+
+        const prebuildTxWithIntent = sandbox.stub(TssUtils.prototype, 'prebuildTxWithIntent');
+        prebuildTxWithIntent.resolves(txRequest);
+
+        const txPrebuild = await tssSolWallet.prebuildTransaction({
+          reqId,
+          recipients,
+          type: 'transfer',
+          isTestTransaction: true,
+        });
+
+        // Verify isTestTransaction is passed to prebuildTxWithIntent
+        sinon.assert.calledOnce(prebuildTxWithIntent);
+        const callArgs = prebuildTxWithIntent.getCall(0).args[0];
+        callArgs.should.have.property('isTestTransaction', true);
+        callArgs.should.have.property('intentType', 'payment');
+        callArgs.should.have.property('recipients');
+        callArgs.recipients.should.deepEqual(recipients);
+
+        txPrebuild.should.deepEqual({
+          walletId: tssSolWallet.id(),
+          wallet: tssSolWallet,
+          txRequestId: 'id',
+          txHex: 'ababcdcd',
+          buildParams: {
+            recipients,
+            type: 'transfer',
+            isTestTransaction: true,
+          },
+          feeInfo: {
+            fee: 5000,
+            feeString: '5000',
+          },
+        });
+      });
+
       it('should build an enable token transaction', async function () {
         const recipients = [];
         const tokenName = 'tcoin:tokenName';

modules/sdk-core/src/bitgo/utils/mpcUtils.ts

@@ -188,6 +188,7 @@ export abstract class MpcUtils {
       nonce: params.nonce,
       recipients: intentRecipients,
       tokenName: params.tokenName,
+      isTestTransaction: params.isTestTransaction,
     };
 
     if (baseCoin.getFamily() === 'eth' || baseCoin.getFamily() === 'polygon' || baseCoin.getFamily() === 'bsc') {

modules/sdk-core/src/bitgo/utils/tss/baseTypes.ts

@@ -269,6 +269,7 @@ export interface PrebuildTransactionWithIntentOptions extends IntentOptionsBase
     abi?: any;
   };
   txRequestId?: string;
+  isTestTransaction?: boolean;
 }
 export interface IntentRecipient {
   address: {
@@ -338,6 +339,7 @@ export interface PopulatedIntent extends PopulatedIntentBase {
    */
   aptosCustomTransactionParams?: aptosCustomTransactionParams;
   txRequestId?: string;
+  isTestTransaction?: boolean;
 }
 
 export type TxRequestState =

modules/sdk-core/src/bitgo/wallet/iWallet.ts

@@ -217,6 +217,7 @@ export interface PrebuildTransactionOptions {
     abi?: any;
   };
   txRequestId?: string;
+  isTestTransaction?: boolean;
 }
 
 export interface PrebuildAndSignTransactionOptions extends PrebuildTransactionOptions, WalletSignTransactionOptions {

modules/sdk-core/src/bitgo/wallet/wallet.ts

@@ -3434,6 +3434,7 @@ export class Wallet implements IWallet {
             custodianTransactionId: params.custodianTransactionId,
             unspents: params.unspents,
             senderAddress: params.senderAddress,
+            isTestTransaction: params.isTestTransaction,
           },
           apiVersion,
           params.preview