rpc: clarify label vs labels in getaddressinfo RPCHelpman

Author: jonatack

src/wallet/rpcwallet.cpp

@@ -3742,15 +3742,16 @@ UniValue getaddressinfo(const JSONRPCRequest& request)
             "                                                         getaddressinfo output fields for the embedded address, excluding metadata (timestamp, hdkeypath,\n"
             "                                                         hdseedid) and relation to the wallet (ismine, iswatchonly).\n"
             "  \"iscompressed\" : true|false,        (boolean, optional) If the pubkey is compressed.\n"
-            "  \"label\" :  \"label\"                  (string) The label associated with the address. Defaults to \"\".\n"
+            "  \"label\" :  \"label\"                  (string) The label associated with the address. Defaults to \"\". Equivalent to the name field in the labels array.\n"
             "  \"timestamp\" : timestamp,            (number, optional) The creation time of the key if available, expressed in seconds since Epoch Time (Jan 1 1970 GMT).\n"
             "  \"hdkeypath\" : \"keypath\"             (string, optional) The HD keypath, if the key is HD and available.\n"
             "  \"hdseedid\" : \"<hash160>\"            (string, optional) The Hash160 of the HD seed.\n"
             "  \"hdmasterfingerprint\" : \"<hash160>\" (string, optional) The fingerprint of the master key.\n"
-            "  \"labels\"                            (object) Array of labels associated with the address.\n"
+            "  \"labels\"                            (object) An array of labels associated with the address. Currently limited to one label but returned\n"
+            "                                               as an array to keep the API stable if multiple labels are enabled in the future.\n"
             "    [\n"
             "      { (json object of label data)\n"
-            "        \"name\": \"label name\" (string) The label.\n"
+            "        \"name\": \"label name\" (string) The label name. Defaults to \"\". Equivalent to the label field above.\n"
             "        \"purpose\": \"purpose\" (string) The purpose of the associated address (send or receive).\n"
             "      },...\n"
             "    ]\n"