* Add AMM bid/create/deposit/swap/withdraw/vote invariants:
- Deposit, Withdrawal invariants: `sqrt(asset1Balance * asset2Balance) >= LPTokens`.
- Bid: `sqrt(asset1Balance * asset2Balance) > LPTokens` and the pool balances don't change.
- Create: `sqrt(asset1Balance * assetBalance2) == LPTokens`.
- Swap: `asset1BalanceAfter * asset2BalanceAfter >= asset1BalanceBefore * asset2BalanceBefore`
and `LPTokens` don't change.
- Vote: `LPTokens` and pool balances don't change.
- All AMM and swap transactions: amounts and tokens are greater than zero, except on withdrawal if all tokens
are withdrawn.
* Add AMM deposit and withdraw rounding to ensure AMM invariant:
- On deposit, tokens out are rounded downward and deposit amount is rounded upward.
- On withdrawal, tokens in are rounded upward and withdrawal amount is rounded downward.
* Add Order Book Offer invariant to verify consumed amounts. Consumed amounts are less than the offer.
* Fix Bid validation. `AuthAccount` can't have duplicate accounts or the submitter account.
* Rename ASSERT to XRPL_ASSERT
* Upgrade to Anthithesis SDK 0.4.4, and use new 0.4.4 features
* automatic cast to bool, like assert
* Add instrumentation workflow to verify build with instrumentation enabled
* Copy Antithesis SDK version 0.4.0 to directory external/
* Add build option `voidstar` to enable instrumentation with Antithesis SDK
* Define instrumentation macros ASSERT and UNREACHABLE in terms of regular C assert
* Replace asserts with named ASSERT or UNREACHABLE
* Add UNREACHABLE to LogicError
* Document instrumentation macros in CONTRIBUTING.md