Integrate the titlebar as part of the top panel on maximize (demo)

[jonchun]

see if I can implement something similar to: https://www.reddit.com/r/kde/comments/futphi/latte_dock_part_of_the_window/fmha4gy/

Not standard in macOS, but it could be a cool/decent alternative to the 2 levels of maximization that exists on macOS that I don't think I'll be able to reproduce in KDE.

[jonchun]

demo'd it out and it looks great.
https://imgur.com/IdQKVV8
(it is not choppy like this normally. i think the screen recording i'm using is buggy)

Will definitely have this as an option to enable. maybe even default.

[jonchun]

Due to this issue n4n0GH/hello#75, need to also install McMojave's Window decorations (Aurorae) if I plan to use this.