WIP making Operation and Precondition smaller

src/main.cpp

@@ -20,8 +20,7 @@ void print_stats(const CommitRequest &request) {
     const auto &op = request.operations()[0];
     std::cout << "  First operation: "
               << (op.type == Operation::Type::Write ? "write" : "other")
-              << " key=" << op.key
-              << " value=" << (op.value ? op.value.value() : "none")
+              << " param1=" << op.param1 << " param2=" << op.param2
               << std::endl;
   }
 }
@@ -85,7 +84,7 @@ int main(int argc, char *argv[]) {
   })";
   auto copy = sample_json;
 
-  if (request.parse_json(copy)) {
+  if (request.parse_json(copy.data(), copy.size())) {
     print_stats(request);
   } else {
     std::cout << "✗ Failed to parse commit request" << std::endl;