qt: Improve user experience on Steam Deck and window managers

[tomboylover93]

This aims to fix issues with the Qt interface on (mostly Linux) desktops that hide the app's titlebar and buttons, such as the Steam Deck's Gaming Mode, which uses Gamescope (see #2086), and the aforementioned window managers. They range from minor quirks to issues that make it outright impossible to perform some actions solely using the GUI, and some examples are:

• the lack of a "Close" button for the Cheats/Patches window, and
• the Settings window resizing itself when hovering over something whose description text occupies more screen real estate than 70px:

Screencast_20250108_134905.mp4

The latter causes weird behavior outside of those desktop interfaces, as when maximizing the Settings window on any desktop environment the text box resizing mechanism does not respect the actual window size, which leads to this:

I'll leave it as a draft for now because I want more input from people using said desktops and other operating systems than Linux, since there might be something I missed or that needs to be changed.

[DanielSvoboda]

Changing bottomMargin from 11 to 190 in UpdateLayout makes it not so stretched

shadPS4/src/qt_gui/settings_dialog.ui

Line 437 in 0c78d0c

<number>11</number>

[GHU7924]

Now the window does not change size and works properly.
The Patches window closes after saving.
It has clearly improved, but there is still such a moment (it's not critical, but it is):

@tomboylover93 To test and get an approximate experience of using the emulator on Steam Deck,
you should change the resolution for the virtual machine.
The Steam Deck has a 16:10 aspect ratio and a resolution of 1280x800.

[tomboylover93]

I don't think I could change much about the drop-down menu resizing the window, that's just how Gamescope is. Though I could make it open upwards instead of downwards.

[GHU7924]

How much and what other edits do you want to make in this PR?

[tomboylover93]

Most of the issues I had were already fixed with the initial commits, I'm leaving it as a draft because maybe someone noticed something that needs to be fixed that I didn't.