[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/qt_common/config/shared_translation.cpp

@@ -47,6 +47,7 @@ std::unique_ptr<TranslationMap> InitializeTranslations(QObject* parent)
     INSERT(Settings, login_share_applet_mode, tr("Login share"), QString());
     INSERT(Settings, wifi_web_auth_applet_mode, tr("Wifi web auth"), QString());
     INSERT(Settings, my_page_applet_mode, tr("My page"), QString());
+    INSERT(Settings, enable_overlay, tr("Enable Overlay Applet"), QString());
 
     // Audio
     INSERT(Settings, sink_id, tr("Output Engine:"), QString());
@@ -732,4 +733,3 @@ std::unique_ptr<ComboboxTranslationMap> ComboboxEnumeration(QObject* parent)
     return translations;
 }
 } // namespace ConfigurationShared
-