Ava UI: Input Menu Refactor (#5826)

* Refactor

* Apply suggestions from code review

Co-authored-by: Ac_K <Acoustik666@gmail.com>

* Update src/Ryujinx/UI/Views/Settings/SettingsHotkeysView.axaml.cs

Co-authored-by: Ac_K <Acoustik666@gmail.com>

* Update src/Ryujinx.Input/ButtonValueType.cs

Co-authored-by: Ac_K <Acoustik666@gmail.com>

* Add empty line

* Requested renames

* Update src/Ryujinx/UI/Views/Settings/SettingsHotkeysView.axaml.cs

Co-authored-by: gdkchan <gab.dark.100@gmail.com>

* Make parent models private readonly

* Fix ControllerInputView

* Make line shorter

* Mac keys in locale

* Double line break

* Fix build

* Get rid of _isValid

* Fix potential race condition

* Rename HasAnyButtonPressed to IsAnyButtonPressed

* Use switches

* Simplify enumeration

---------

Co-authored-by: Ac_K <Acoustik666@gmail.com>
Co-authored-by: gdkchan <gab.dark.100@gmail.com>
Co-authored-by: TSR Berry <20988865+TSRBerry@users.noreply.github.com>

src/Ryujinx.Common/Configuration/Hid/KeyboardHotkeys.cs

@@ -1,7 +1,5 @@
 namespace Ryujinx.Common.Configuration.Hid
 {
-    // NOTE: Please don't change this to struct.
-    //       This breaks Avalonia's TwoWay binding, which makes us unable to save new KeyboardHotkeys.
     public class KeyboardHotkeys
     {
         public Key ToggleVsync { get; set; }