fix(TXL-399): Use contract abi to decode the amounts of token balance changes

[dbrans]

Explanation

• Use contract abi's to decode the amounts of token balance changes – instead of the raw output from a balanceOf call.

References

• Fixes: [Bug]: Wrong token amount for vUSDC minting and withdrawing on Venus metamask-extension#26521

Changelog

@metamask/transaction-controller

• FIXED: Use contract abi's to decode the amounts of token balance changes – instead of the raw output from a balanceOf call.

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 highlighted breaking changes using the "BREAKING" category above as appropriate
• I've prepared draft pull requests for clients and consumer packages to resolve any breaking changes

[sleepytanya]

Accurate token amount and fiat price for vUSDC:

vusdc.mov

[matthewwalsh0]

We want to limit the public API as much as possible, so can we avoid exporting this purely for the sake of a unit test, and instead verify any new logic via a call to getSimulationData?