Output psbt version in decodepsbt

src/rpc/rawtransaction.cpp

@@ -1075,6 +1075,7 @@ static RPCHelpMan decodepsbt()
                         {
                             {RPCResult::Type::ELISION, "", "The layout is the same as the output of decoderawtransaction."},
                         }},
+                        {RPCResult::Type::NUM, "psbt_version", "The PSBT version number. Not to be confused with the unsigned transaction version"},
                         {RPCResult::Type::OBJ_DYN, "unknown", "The unknown global fields",
                         {
                              {RPCResult::Type::STR_HEX, "key", "(key-value pair) An unknown key-value pair"},
@@ -1194,6 +1195,9 @@ static RPCHelpMan decodepsbt()
     TxToUniv(CTransaction(*psbtx.tx), uint256(), tx_univ, false);
     result.pushKV("tx", tx_univ);
 
+    // PSBT version
+    result.pushKV("psbt_version", static_cast<uint64_t>(psbtx.GetVersion()));
+
     // Unknown data
     UniValue unknowns(UniValue::VOBJ);
     for (auto entry : psbtx.unknown) {