fix: quote request should not be sent of amount of token requested by the user is 0

[jpuri]

Explanation

Money account page updated transaction a few times, this change ensure that we get quote only of token amount requested is not 0.

References

Fixes https://consensyssoftware.atlassian.net/browse/CONF-1241

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

---

Note

Medium Risk
Changes required-token detection logic used to drive quoting/payment flows; consumers that relied on the synthetic gas-fee token may see different quote requests and balance checks.

Overview
parseRequiredTokens no longer synthesizes/returns a native “gas fee required token”; when requiredAssets are absent it now only returns a required token for detected ERC-20 transfer data (otherwise []).

This removes the getGasFeeToken code path (and related BigNumber/native-token helpers), updates unit tests to drop gas-fee expectations and assert empty results for invalid transfer data, and documents the behavioral change in the changelog.

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[jpuri]

On money account page token / accountOverride can be updated few times. We need to ensure that quotes is not refetched unless user enters a non-zero token amount. Thus this change is made.

Another approach could be to change methods setTransactionConfig, 'setPaymentToken' to not refresh quote is amount of token requested is zero.

[matthewwalsh0]

We already have this logic in source-amounts.ts, so this was working previously, so is this a unique issue for account override somehow?

[jpuri]

When we update transactionConfig - like update accountOverride, it triggers updating payToken and getting new quote. So this was happening frequently on money account pages.

Also, money account transaction I found was request 0 value for required token and a small value for another token with token.skipIfBalance true. I guess it was for gas fees.

[matthewwalsh0]

But we only generate quote requests for any source amounts we have, and the logic in calculatePostQuoteSourceAmounts should already skip tokens if its skipIfBalance or if the amount is zero?

So we need to debug why that existing logic isn't working.

[jpuri]

Yep, let me debug existing code.

[jpuri]

I found that we are updating source amount here:

core/packages/transaction-pay-controller/src/TransactionPayController.ts

Line 258 in 3733d0c

updateSourceAmounts(transactionId, current as never, this.messenger);

But despite zero amount we send request to api.

I think we can simplify code added in this PR to just check if all sourceAmounts are '0' we do not send request.

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