Closes #60013

# Objective

Right now Zed can go full screen but it does not allow you to fix the
hole screen,
by that I mean that Zed can go behind the notch so you don't have extra
useless room left.

## Solution

You can now use the `fullscreen_mode` = `simple` setting to use the new
simple full screen feature, that lives besides the normal full screen
feature. But allows you to have an option to go 100% full screen without
losing any useless space on your macbook screen.
**Note** this is mostly usefull when you have a macbook that has a notch
whitch is kinda in the way of your work flow.

## Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [x] Unsafe blocks (if any) have justifying comments
- [x] The content adheres to Zed's UI standards
([UX/UI](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
and
[icon](https://github.com/zed-industries/zed/blob/main/crates/icons/README.md)
guidelines)
- [x] Tests cover the new/changed behavior
- [x] Performance impact has been considered and is acceptable

## Showcase

**Before**
<img width="5712" height="4284" alt="IMG_0339"
src="https://github.com/user-attachments/assets/9f908ffd-7cef-4999-a454-c80f72c40dc8"
/>

**After** (Note now Zed is behind your notch when using the simple full
screen feature)
<img width="5712" height="4284" alt="IMG_0360"
src="https://github.com/user-attachments/assets/5917ed4d-2a64-4464-a794-bc46fd034521"
/>


---

Release Notes:

- Added support for simple fullscreen mode using the `fullscreen_mode`
setting, set it to `simple` to try it out.