* new videos
* now video extraction can be stepped thru with undo redo, and is savable in save scene
* organize the code for making commands for undo-redo, now add/remove of chroma key is also recorded in the stack
* plumbbing datat from upload ui to video node to saving and loading the node
* new videos have loading screen
* make sizing of loading video fits the save video and retry for playing the loading screen
* better loading bar setup
wil
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