[Feature] Integrated borderless fullscreen windows

Is your feature request related to a problem? Please describe.
currently maximized windows dont play too nicely with karousel and either get:
excluded from the tiling grid and placed above (eg. Bomb Rush cyberfunk from steam)
un-fullscreened when switching windows (eg. youtube)

Describe the solution you'd like
a really nice approach ive seen (for example in paperwm and niri) is having the fullscreen window act as an unresizable monitor-length window which can be moved around.

^heres a crude drawing i did to demonstrate what i mean and [here](https://www.youtube.com/watch?v=N_phrNKs3PI&t=19s/) at 9:55 is a clip of brodie robertson demonstrating what i mean

Describe alternatives you've considered
I could just keep using it the way it is now (Implementing something like this seems VERY tricky) but this is one of (but defintely not the only) things that sold me on the scrolling model

Additional context
funfact celeste is goated and works great with karousel.

Id be glad to do testing and try out builds but i severely lack dev knowledge so keep in that in mind :P
TYSM for this project im in love w it ure very cool

The issue does not name files or tests. Start by locating the existing maximized and fullscreen-window handling in the TypeScript code, then trace how those windows enter the tiling grid. Done means fullscreen windows behave as movable, monitor-length tiled windows without being excluded or un-fullscreened when switching.