[SMTChecker] Verify Chai

https://github.com/dapphub/chai/blob/master/src/chai.sol

@MrChico any insights on what we could try to verify here?
I guess most stuff might be too hard anyway given the amount of math in the contract.

Start by reading the Chai contract at https://github.com/dapphub/chai/blob/master/src/chai.sol and the Solidity SMTChecker context around this issue. Identify which properties of the contract could be verified and whether the existing checker can handle its mathematical complexity. The issue does not define a specific property or completion criterion.

Written by the indexing model from the issue text.