docs: private void generateExtensibilityMethods(
          final StringBuilder sb,
          final String typeName,
          final Token token)
      {
          sb.append(String.format(
              "\nfunc (*%1$s) SbeBlockLength() (blockLength uint) {\n" +
              "\treturn %2$s\n" +
              "}\n" +
              "\nfunc (*%1$s) SbeSchemaVersion() (schemaVersion %3$s) {\n" +
              "\treturn %4$s\n" +
              "}\n",
              typeName,
              generateLiteral(ir.headerStructure().blockLengthType(), Integer.toString(token.encodedLength())),
              golangTypeName(ir.headerStructure().schemaVersionType()),
              generateLiteral(ir.headerStructure().schemaVersionType(), Integer.toString(ir.version()))));
      }