[Bug]: `Erc20Wrapper::_recover` Should Bubble Up the Underlying Error on `balance_of`

[0xNeshi]

What happened?

We currently return ERC20InvalidUnderlying { token: contract_address } on error, which is problematic for 2 reasons:

1. This doesn't align with Solidity behavior.
2. The "invalid underlying token" should be token: underlying_token, not token: contract_address (i.e. wrapper address).

platform

• linux
• windows
• macos

Expected behavior

Update the Wrapper to return Vec<u8> on all functions, enabling errors bubbling up.

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