[zksend] fix import paths (MystenLabs#15640)

## Description 

Describe the changes or additions included in this PR.

## Test Plan 

How did you test the new or updated feature?

---
If your changes are not user-facing and do not break anything, you can
skip the following section. Otherwise, please briefly describe what has
changed under the Release Notes section.

### Type of Change (Check all that apply)

- [ ] protocol change
- [ ] user-visible impact
- [ ] breaking change for a client SDKs
- [ ] breaking change for FNs (FN binary must upgrade)
- [ ] breaking change for validators or node operators (must upgrade
binaries)
- [ ] breaking change for on-chain data layout
- [ ] necessitate either a data wipe or data migration

### Release notes

.changeset/strong-kings-clap.md

@@ -0,0 +1,5 @@
+---
+'@mysten/zksend': patch
+---
+
+Fix import paths

dapps/sponsored-transactions/src/utils/sponsorTransaction.ts

@@ -1,9 +1,9 @@
 // Copyright (c) Mysten Labs, Inc.
 // SPDX-License-Identifier: Apache-2.0
 
+import { SuiObjectRef } from '@mysten/sui.js/client';
 import { getFaucetHost, requestSuiFromFaucetV1 } from '@mysten/sui.js/faucet';
 import { Ed25519Keypair } from '@mysten/sui.js/keypairs/ed25519';
-import { SuiObjectRef } from '@mysten/sui.js/src/types/objects';
 import { TransactionBlock } from '@mysten/sui.js/transactions';
 
 import { client } from './rpc';

sdk/zksend/src/links.ts

@@ -1,13 +1,12 @@
 // Copyright (c) Mysten Labs, Inc.
 // SPDX-License-Identifier: Apache-2.0
 
-import { URL } from 'url';
+import { getFullnodeUrl, SuiClient } from '@mysten/sui.js/client';
+import type { SuiObjectChange } from '@mysten/sui.js/client';
+import type { Keypair } from '@mysten/sui.js/cryptography';
 import { Ed25519Keypair } from '@mysten/sui.js/keypairs/ed25519';
-import type { TransactionObjectInput } from '@mysten/sui.js/src/builder';
-import { TransactionBlock } from '@mysten/sui.js/src/builder';
-import type { SuiObjectChange } from '@mysten/sui.js/src/client';
-import { getFullnodeUrl, SuiClient } from '@mysten/sui.js/src/client';
-import type { Keypair } from '@mysten/sui.js/src/cryptography';
+import type { TransactionObjectInput } from '@mysten/sui.js/transactions';
+import { TransactionBlock } from '@mysten/sui.js/transactions';
 import {
 	fromB64,
 	normalizeStructTag,

sdk/zksend/src/wallet.ts

@@ -1,8 +1,8 @@
 // Copyright (c) Mysten Labs, Inc.
 // SPDX-License-Identifier: Apache-2.0
 
+import { bcs } from '@mysten/sui.js/bcs';
 import { getFullnodeUrl, SuiClient } from '@mysten/sui.js/client';
-import { bcs } from '@mysten/sui.js/src/bcs/index.js';
 import { toB64 } from '@mysten/sui.js/utils';
 import type {
 	StandardConnectFeature,