Update main branch w/ demo version

[cwlacewe]

The overall flow of application has changed and now leverages fastapi.
This version is ready for demo and can be merged into main.

There is still room for improvement:

• Investigate any instances (if any) of thread deadlocks or insufficient hardware resources OR adjust # of threads/buffer sizes
• Improve VDMS ingestion (experiencing LockTimeouts)
• Improve GPU pipeline to eliminate/minimize tearing in mask frames
• Reach performance goal of running 1 hr (90% success)
• Improve CPU pipeline to increase processing rate (if possible)

[s-gobriel]

I see a lot of threads being created, communicating on shared memory and hardware resources are pre-allocated. I don't know if there will be deadlocks but if the demo runs fine then no need to debug all the cases unless there are some issue with the threading. .. Can we track visually the area submitted to object tracking (not objects discovered) .. I want to make sure that for each frame there is some area being sent to YOLO for each frame and no frame is skipped because the threads are blocked ... maybe you can also explain to me how we are queuing the frames and what will happen if this queue is building up in the pipeline