replay: fix missing events before INIT_DATA (#30039)

fix missing events

tools/replay/replay.cc

@@ -321,13 +321,12 @@ void Replay::mergeSegments(const SegmentMap::iterator &begin, const SegmentMap::
 void Replay::startStream(const Segment *cur_segment) {
   const auto &events = cur_segment->log->events;
 
-  // get route start time from initData
-  auto it = std::find_if(events.begin(), events.end(), [](auto e) { return e->which == cereal::Event::Which::INIT_DATA; });
-  route_start_ts_ = it != events.end() ? (*it)->mono_time : events[0]->mono_time;
-  cur_mono_time_ += route_start_ts_;
+  // each segment has an INIT_DATA
+  route_start_ts_ = events.front()->mono_time;
+  cur_mono_time_ += route_start_ts_ - 1;
 
   // write CarParams
-  it = std::find_if(events.begin(), events.end(), [](auto e) { return e->which == cereal::Event::Which::CAR_PARAMS; });
+  auto it = std::find_if(events.begin(), events.end(), [](auto e) { return e->which == cereal::Event::Which::CAR_PARAMS; });
   if (it != events.end()) {
     car_fingerprint_ = (*it)->event.getCarParams().getCarFingerprint();
     capnp::MallocMessageBuilder builder;