fix(transaction-pay-controller): account override fixes (#8724)

## Summary

Fixes in `transaction-pay-controller`'s Relay strategy that together
unblock Money Account deposits via MetaMask Pay (and any other
delegation-based deposit flow targeting Arbitrum USDC).

1. Funding-leg recipient should be `transaction.txParams.from`, not
`request.from`
2. Arbitrum-USDC → Hypercore rewrite must be gated on `perpsDeposit`

Ref: https://consensyssoftware.atlassian.net/browse/CONF-1324

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Medium Risk**
> Adjusts Relay quote transaction construction and chain/token rewrite
behavior for Arbitrum USDC deposits; mistakes here could misroute funds
or produce incorrect quotes for delegation-based flows.
> 
> **Overview**
> Fixes Relay quoting for delegation-based flows when `accountOverride`
causes `request.from` to differ from the executing delegator.
> 
> Relay now funds the **delegator address**
(`transaction.txParams.from`) when building the initial token-transfer
leg (falling back to `request.from` if unset), and the Arbitrum-USDC →
Hypercore (Hyperliquid) quote rewrite is now **only applied for
`TransactionType.perpsDeposit`** (not for other transaction types or
post-quote flows). Tests and the changelog are updated to cover these
cases.
> 
> <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit
882ea79. Bugbot is set up for automated
code reviews on this repo. Configure
[here](https://www.cursor.com/dashboard/bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

---------

Co-authored-by: Jyoti Puri <jyotipuri@gmail.com>

Author: matthewwalsh0

packages/transaction-pay-controller/CHANGELOG.md

@@ -7,6 +7,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+
+- Fix transaction with accountOverride and targeting Arbitrum USDC ([#8724](https://github.com/MetaMask/core/pull/8724))
+  - Deliver the Relay-acquired token to `transaction.txParams.from` (the delegator that executes the inner delegation), not `request.from`.
+  - Gate the Arbitrum-USDC → Hypercore quote rewrite on `transaction.type === TransactionType.perpsDeposit`.
+
 ## [22.0.2]
 
 ### Changed

packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts

@@ -454,6 +454,68 @@ describe('Relay Quotes Utils', () => {
       );
     });
 
+    it('funds the delegator (transaction.txParams.from) rather than request.from when they differ', async () => {
+      const delegatorAddress =
+        '0xabcdef0000000000000000000000000000000001' as Hex;
+
+      successfulFetchMock.mockResolvedValue({
+        ok: true,
+        json: async () => QUOTE_MOCK,
+      } as never);
+
+      await getRelayQuotes({
+        accountSupports7702: true,
+        messenger,
+        requests: [QUOTE_REQUEST_MOCK],
+        transaction: {
+          ...TRANSACTION_META_MOCK,
+          txParams: {
+            from: delegatorAddress,
+            data: '0xabc' as Hex,
+          },
+        } as TransactionMeta,
+      });
+
+      const body = JSON.parse(
+        successfulFetchMock.mock.calls[0][1]?.body as string,
+      );
+
+      expect(body.txs[0]).toStrictEqual({
+        to: QUOTE_REQUEST_MOCK.targetTokenAddress,
+        data: '0xa9059cbb000000000000000000000000abcdef0000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000007b',
+        value: '0x0',
+      });
+    });
+
+    it('falls back to request.from for the funding recipient when transaction.txParams.from is unset', async () => {
+      successfulFetchMock.mockResolvedValue({
+        ok: true,
+        json: async () => QUOTE_MOCK,
+      } as never);
+
+      await getRelayQuotes({
+        accountSupports7702: true,
+        messenger,
+        requests: [QUOTE_REQUEST_MOCK],
+        transaction: {
+          ...TRANSACTION_META_MOCK,
+          txParams: {
+            data: '0xabc' as Hex,
+          },
+        } as TransactionMeta,
+      });
+
+      const body = JSON.parse(
+        successfulFetchMock.mock.calls[0][1]?.body as string,
+      );
+
+      expect(body.txs[0]).toStrictEqual({
+        to: QUOTE_REQUEST_MOCK.targetTokenAddress,
+        data: '0xa9059cbb0000000000000000000000001234567890123456789012345678901234567891000000000000000000000000000000000000000000000000000000000000007b',
+        value: '0x0',
+      });
+    });
+
     it('includes request in quote', async () => {
       successfulFetchMock.mockResolvedValue({
         ok: true,
@@ -2751,7 +2813,10 @@ describe('Relay Quotes Utils', () => {
         accountSupports7702: true,
         messenger,
         requests: [arbitrumToHyperliquidRequest],
-        transaction: TRANSACTION_META_MOCK,
+        transaction: {
+          ...TRANSACTION_META_MOCK,
+          type: TransactionType.perpsDeposit,
+        },
       });
 
       const body = JSON.parse(
@@ -2767,6 +2832,37 @@ describe('Relay Quotes Utils', () => {
       );
     });
 
+    it('does not convert to Hyperliquid deposit when parent transaction is not a Perps deposit', async () => {
+      const arbitrumUsdcRequest: QuoteRequest = {
+        ...QUOTE_REQUEST_MOCK,
+        targetChainId: CHAIN_ID_ARBITRUM,
+        targetTokenAddress: ARBITRUM_USDC_ADDRESS,
+      };
+
+      successfulFetchMock.mockResolvedValue({
+        ok: true,
+        json: async () => QUOTE_MOCK,
+      } as never);
+
+      await getRelayQuotes({
+        accountSupports7702: true,
+        messenger,
+        requests: [arbitrumUsdcRequest],
+        transaction: TRANSACTION_META_MOCK,
+      });
+
+      const body = JSON.parse(
+        successfulFetchMock.mock.calls[0][1]?.body as string,
+      );
+
+      expect(body).toStrictEqual(
+        expect.objectContaining({
+          destinationChainId: Number(CHAIN_ID_ARBITRUM),
+          destinationCurrency: ARBITRUM_USDC_ADDRESS,
+        }),
+      );
+    });
+
     it('does not convert to Hyperliquid deposit for post-quote requests targeting Arbitrum USDC', async () => {
       const postQuoteRequest: QuoteRequest = {
         ...QUOTE_REQUEST_MOCK,

packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts

@@ -2,6 +2,7 @@
 
 import { Interface } from '@ethersproject/abi';
 import { toHex } from '@metamask/controller-utils';
+import { TransactionType } from '@metamask/transaction-controller';
 import type { TransactionMeta } from '@metamask/transaction-controller';
 import type { Hex } from '@metamask/utils';
 import { createModuleLogger } from '@metamask/utils';
@@ -87,7 +88,9 @@ export async function getRelayQuotes(
 
         return hasTargetMinimum || isPostQuote || isExactInputRequest;
       })
-      .map((singleRequest) => normalizeRequest(singleRequest));
+      .map((singleRequest) =>
+        normalizeRequest(singleRequest, request.transaction),
+      );
 
     log('Normalized requests', normalizedRequests);
 
@@ -346,10 +349,15 @@ async function processTransactions(
     requestBody.refundTo = request.from;
   }
 
+  const fundingRecipient = (transaction.txParams?.from as Hex) ?? request.from;
+
   requestBody.txs = [
     {
       to: request.targetTokenAddress,
-      data: buildTokenTransferData(request.from, request.targetAmountMinimum),
+      data: buildTokenTransferData(
+        fundingRecipient,
+        request.targetAmountMinimum,
+      ),
       value: '0x0',
     },
     {
@@ -364,14 +372,22 @@ async function processTransactions(
  * Normalizes requests for Relay.
  *
  * @param request - Quote request to normalize.
+ * @param transaction - Parent transaction metadata, used to gate
+ * Hyperliquid-specific rewrites on transaction type.
  * @returns Normalized request.
  */
-function normalizeRequest(request: QuoteRequest): QuoteRequest {
+function normalizeRequest(
+  request: QuoteRequest,
+  transaction: TransactionMeta,
+): QuoteRequest {
   const newRequest = {
     ...request,
   };
 
+  const isPerpsDeposit = transaction.type === TransactionType.perpsDeposit;
+
   const isHyperliquidDeposit =
+    isPerpsDeposit &&
     !request.isPostQuote &&
     request.targetChainId === CHAIN_ID_ARBITRUM &&
     request.targetTokenAddress.toLowerCase() ===