refactor ui

- Implemented CustomTab class with notification support and custom painting.
- Created CustomTabWidget to manage multiple tabs with a stacked widget layout.
- Integrated glider animation for smooth tab transitions.
- Updated DeviceInfoWidget to improve layout and visual appearance with shadows.
- Refactored DeviceMenuWidget to use QStackedWidget instead of QTabWidget for better flexibility.
- Enhanced main window setup with custom tab widget and improved device management UI.
- Added macOS specific window styling for a more native look.
- Improved ToolboxWidget layout and styling for better user experience.

src/appcontext.cpp

@@ -153,6 +153,11 @@ void AppContext::instanceRemoveDevice(QString _udid)
     // return true;
 }
 
+int AppContext::getConnectedDeviceCount() const
+{
+    return m_devices.size() + m_recoveryDevices.size();
+}
+
 void AppContext::removeDevice(QString _udid)
 
 {