Replace boost with C++17 std equivalents, upgrade LZ4 to 1.10.0

- boost::tuple → std::tuple (serialize.h, miner.cpp, script.cpp, walletdb.cpp)
- boost::shared_ptr → std::shared_ptr (trianglesrpc.cpp)
- boost::variant → std::variant for CTxDestination (script.h)
- boost::get → std::get_if (main.cpp, rpcblockchain.cpp, coincontroldialog.cpp, wallet.cpp)
- boost::apply_visitor → std::visit (base58.h, script.cpp, rpcwallet.cpp, test/base58_tests.cpp)
- boost::static_visitor removed from all visitor classes
- boost::lexical_cast → std::to_string/std::stoll (smessage.cpp, rpcsmessage.cpp)
- Removed unused boost/lexical_cast.hpp includes (rest.cpp, trianglesrpc.cpp)
- Removed boost/variant/get.hpp include (rpcdump.cpp)
- Upgraded vendored LZ4 from 1.1.3 to 1.10.0
- Updated LZ4_compress() → LZ4_compress_default() (smessage.cpp)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/walletdb.cpp

@@ -47,7 +47,7 @@ bool CWalletDB::WriteAccount(const string& strAccount, const CAccount& account)
 
 bool CWalletDB::WriteAccountingEntry(const uint64_t nAccEntryNum, const CAccountingEntry& acentry)
 {
-    return Write(boost::make_tuple(string("acentry"), acentry.strAccount, nAccEntryNum), acentry);
+    return Write(std::make_tuple(string("acentry"), acentry.strAccount, nAccEntryNum), acentry);
 }
 
 bool CWalletDB::WriteAccountingEntry(const CAccountingEntry& acentry)
@@ -80,7 +80,7 @@ void CWalletDB::ListAccountCreditDebit(const string& strAccount, list<CAccountin
         // Read next record
         CDataStream ssKey(SER_DISK, CLIENT_VERSION);
         if (fFlags == DB_SET_RANGE)
-            ssKey << boost::make_tuple(string("acentry"), (fAllAccounts? string("") : strAccount), uint64_t(0));
+            ssKey << std::make_tuple(string("acentry"), (fAllAccounts? string("") : strAccount), uint64_t(0));
         CDataStream ssValue(SER_DISK, CLIENT_VERSION);
         int ret = ReadAtCursor(pcursor, ssKey, ssValue, fFlags);
         fFlags = DB_NEXT;