Add recording to Shared Memory

src/config.hpp

@@ -61,6 +61,8 @@ struct AppConfig {
     bool record_video = false;
     int video_segment_sec = 3600;
     int output_fps = 15;
+    float record_delay_seconds = 10.0f;
+    std::string record_shm_dir = "/dev/shm/bytetrack-counter";
 
     bool live_stream_enabled = false;
     std::string live_stream_frame_path = "/dev/shm/bytetrack-counter/live_frame.jpg";