[Feature Request] Allow integrating video chapters to be saved into video

[zixinus]

Pretty much what is in the title. It would be great if the chapters of a a video (the timecode-based labels that you can see in the progress bar) to be an option to integrate into the videos themselves.

PS: I admit I don't know how modern formats support this or whether the parts that make ytdownloader also support this.

[aandrew-me]

Possible, I will add it