Support to pausing and resuming execution

[pozitronik]

The main idea is to give users the possibility to interrupt the current process and resume it later. This can be implemented through files that store the process's current state, including the parameters it was launched with, the current step, the frame number at which the replacement process was interrupted, and more. By default, such a file can be saved in the script directory and automatically loaded on the next run, allowing the process to continue from where it was stopped. Alternatively, the path to such a file can be passed as a parameter.

The idea can also be implemented by simply specifying launch parameters. For example: python run.py --face="face_path.jpg" --target="target_path.mp4" --output="result_path.mp4" --resume=swapping --frame=100500

I think, you got the idea.