Introduce AMM support (XLS-30d): (#4294)

Add AMM functionality:
- InstanceCreate
- Deposit
- Withdraw
- Governance
- Auctioning
- payment engine integration

To support this functionality, add:
- New RPC method, `amm_info`, to fetch pool and LPT balances
- AMM Root Account
- trust line for each IOU AMM token
- trust line to track Liquidity Provider Tokens (LPT)
- `ltAMM` object

The `ltAMM` object tracks:
- fee votes
- auction slot bids
- AMM tokens pair
- total outstanding tokens balance
- `AMMID` to AMM `RootAccountID` mapping

Add new classes to facilitate AMM integration into the payment engine.
`BookStep` uses these classes to infer if AMM liquidity can be consumed.

The AMM formula implementation uses the new Number class added in #4192.
IOUAmount and STAmount use Number arithmetic.

Add AMM unit tests for all features.

AMM requires the following amendments:
- featureAMM
- fixUniversalNumber
- featureFlowCross

Notes:
- Current trading fee threshold is 1%
- AMM currency is generated by: 0x03 + 152 bits of sha256{cur1, cur2}
- Current max AMM Offers is 30

---------

Co-authored-by: Howard Hinnant <howard.hinnant@gmail.com>

src/ripple/protocol/impl/STIssue.cpp

@@ -0,0 +1,113 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of rippled: https://github.com/ripple/rippled
+    Copyright (c) 2023 Ripple Labs Inc.
+
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose  with  or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#include <ripple/protocol/STIssue.h>
+
+#include <ripple/basics/contract.h>
+
+namespace ripple {
+
+STIssue::STIssue(SField const& name) : STBase{name}
+{
+}
+
+STIssue::STIssue(SerialIter& sit, SField const& name) : STBase{name}
+{
+    issue_.currency = sit.get160();
+    if (!isXRP(issue_.currency))
+        issue_.account = sit.get160();
+    else
+        issue_.account = xrpAccount();
+
+    if (isXRP(issue_.currency) != isXRP(issue_.account))
+        Throw<std::runtime_error>(
+            "invalid issue: currency and account native mismatch");
+}
+
+STIssue::STIssue(SField const& name, Issue const& issue)
+    : STBase{name}, issue_{issue}
+{
+    if (isXRP(issue_.currency) != isXRP(issue_.account))
+        Throw<std::runtime_error>(
+            "invalid issue: currency and account native mismatch");
+}
+
+SerializedTypeID
+STIssue::getSType() const
+{
+    return STI_ISSUE;
+}
+
+std::string
+STIssue::getText() const
+{
+    return issue_.getText();
+}
+
+Json::Value STIssue::getJson(JsonOptions) const
+{
+    return to_json(issue_);
+}
+
+void
+STIssue::add(Serializer& s) const
+{
+    s.addBitString(issue_.currency);
+    if (!isXRP(issue_.currency))
+        s.addBitString(issue_.account);
+}
+
+bool
+STIssue::isEquivalent(const STBase& t) const
+{
+    const STIssue* v = dynamic_cast<const STIssue*>(&t);
+    return v && (*v == *this);
+}
+
+bool
+STIssue::isDefault() const
+{
+    return issue_ == xrpIssue();
+}
+
+std::unique_ptr<STIssue>
+STIssue::construct(SerialIter& sit, SField const& name)
+{
+    return std::make_unique<STIssue>(sit, name);
+}
+
+STBase*
+STIssue::copy(std::size_t n, void* buf) const
+{
+    return emplace(n, buf, *this);
+}
+
+STBase*
+STIssue::move(std::size_t n, void* buf)
+{
+    return emplace(n, buf, std::move(*this));
+}
+
+STIssue
+issueFromJson(SField const& name, Json::Value const& v)
+{
+    return STIssue{name, issueFromJson(v)};
+}
+
+}  // namespace ripple