Common macOS Windowing Features

Fluxer is missing several windowing features that many macOS programs incorporate. In particular, the "Fill" feature--which I use fairly often with the shortcut Fn+Ctrl+F--to maximize the window (separate from the "Zoom" feature).

Implement "Fill", "Center", and the various tiling shortcuts present today in many macOS apps.

I have attached screenshots of the macOS menu bar "Window" tab in Fluxer vs Discord to highlight the difference. (Modded Discord, but I believe the menu items are identical to stock Discord.)