[hle,display,overlay,starter,hid] add overlay functions, starter applet (initially), HID handheld for system applets and fw21 stubs (#3080)

Adds fully functional overlay display.
- Enable Overlay Applet via "View" -> "Enable Overlay Display Applet"
- Open the overlay by pressing the home button for over 1s
- Can adjust volume
- Can toggle airplane mode (if on WiFi, maybe if overlay is enabled pretend to be on WiFi?)
- Future TODO(?): Adjust Brightness implementation for host system
- Inputs are properly registered. e.g. if overlay open, application does not register inputs.

You can control volume and airplane mode outside of the emulator window

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3080
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Reviewed-by: crueter <crueter@eden-emu.dev>
Co-authored-by: Maufeat <sahyno1996@gmail.com>
Co-committed-by: Maufeat <sahyno1996@gmail.com>

src/yuzu/main.ui

@@ -131,7 +131,7 @@
     </action>
     <addaction name="action_Fullscreen"/>
     <addaction name="action_Single_Window_Mode"/>
-    <addaction name="action_Display_Dock_Widget_Headers"/>
+    <addaction name="action_Enable_Overlay_Applet"/>
     <addaction name="action_Show_Filter_Bar"/>
     <addaction name="action_Show_Status_Bar"/>
     <addaction name="separator"/>
@@ -298,12 +298,12 @@
     <enum>QAction::MenuRole::PreferencesRole</enum>
    </property>
   </action>
-  <action name="action_Display_Dock_Widget_Headers">
+  <action name="action_Enable_Overlay_Applet">
    <property name="checkable">
     <bool>true</bool>
    </property>
    <property name="text">
-    <string>Display D&amp;ock Widget Headers</string>
+    <string>Enable Overlay Display Applet</string>
    </property>
   </action>
   <action name="action_Show_Filter_Bar">