Add Clone, Add, and Save to the fullscreen resource editor

[grantfitzsimmons]

Discussed in #3767

^{Originally posted by grantfitzsimmons July 11, 2023}

How it looks now:

How it should look:

It's inconvenient to need to leave full screen, click save, then go back into full screen editing. The "Close" button is redundant since there is a fullscreen icon in the top level menu. It's logical to click the button you clicked to go full screen to minimize again.

[maxpatiiuk]

I think this also fixes a UX problem with the current design: having just a Close button, and no Save button makes users feel like their changes won't be saved.

Also, the Close button was redundant with the full screen exit button.

I think we should definitely do the change you proposed, assuming it is not too difficult in the code (I don't remember the code, but probably the 3 buttons could just be assigned to a variable, and that variable could be put in a different place depending if you are in full screen or not)