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/test/base58_tests.cpp

@@ -58,7 +58,7 @@ BOOST_AUTO_TEST_CASE(base58_DecodeBase58)
 }
 
 // Visitor to check address type
-class TestAddrTypeVisitor : public boost::static_visitor<bool>
+class TestAddrTypeVisitor
 {
 private:
     std::string exp_addrType;
@@ -79,7 +79,7 @@ public:
 };
 
 // Visitor to check address payload
-class TestPayloadVisitor : public boost::static_visitor<bool>
+class TestPayloadVisitor
 {
 private:
     std::vector<unsigned char> exp_payload;
@@ -150,7 +150,7 @@ BOOST_AUTO_TEST_CASE(base58_keys_valid_parse)
             BOOST_CHECK_MESSAGE(addr.IsValid(), "!IsValid:" + strTest);
             BOOST_CHECK_MESSAGE(addr.IsScript() == (exp_addrType == "script"), "isScript mismatch" + strTest);
             CTxDestination dest = addr.Get();
-            BOOST_CHECK_MESSAGE(boost::apply_visitor(TestAddrTypeVisitor(exp_addrType), dest), "addrType mismatch" + strTest);
+            BOOST_CHECK_MESSAGE(std::visit(TestAddrTypeVisitor(exp_addrType), dest), "addrType mismatch" + strTest);
 
             // Public key must be invalid private key
             secret.SetString(exp_base58string);
@@ -213,7 +213,7 @@ BOOST_AUTO_TEST_CASE(base58_keys_valid_gen)
                 continue;
             }
             CTrianglesAddress addrOut;
-            BOOST_CHECK_MESSAGE(boost::apply_visitor(CTrianglesAddressVisitor(&addrOut), dest), "encode dest: " + strTest);
+            BOOST_CHECK_MESSAGE(std::visit(CTrianglesAddressVisitor(&addrOut), dest), "encode dest: " + strTest);
             BOOST_CHECK_MESSAGE(addrOut.ToString() == exp_base58string, "mismatch: " + strTest);
         }
     }
@@ -221,7 +221,7 @@ BOOST_AUTO_TEST_CASE(base58_keys_valid_gen)
     // Visiting a CNoDestination must fail
     CTrianglesAddress dummyAddr;
     CTxDestination nodest = CNoDestination();
-    BOOST_CHECK(!boost::apply_visitor(CTrianglesAddressVisitor(&dummyAddr), nodest));
+    BOOST_CHECK(!std::visit(CTrianglesAddressVisitor(&dummyAddr), nodest));
 
     // Restore global state
     fTestNet = fTestNet_stored;