Support state changes comparison for differential fuzzing

[suxnju]

Describe the desired feature

In some scenarios, we want to compare whether the upgraded contract has changed the same states (not limited to return values).

For example, the following code snippet deleted a sentence because of carelessness after upgrading.

uint256 value = balanceOf[msg.sender];
- balanceOf[msg.sender] = 0; // deleted carelessly
(bool success, ) = msg.sender.call{value: value}("");

As far as I know, it is possible to compare whether the state changes are consistent in fuzzing. One feasible idea is to use foundry's startStateDiffRecording and stopAndReturnStateDiff.

However, as I am new to this field, I wonder if there is a simple way to support this based on diffusc.