Fix or improve error message vulcan.fmt._readSlice(bytes,uint256,uint256): Slice out of bounds

[vdrg]

Reproduce:

bytes32 a = bytes32("hello");
// a is not bytes so this happens
println("{b}", abi.encode(a));

We need to decide if we want to handle this in some way or just provide a better error message with suggestions.

[vdrg]

@gnkz should we close this?

[gnkz]

@gnkz should we close this?

Not yet, will work on this soon