Refactor EventEmitter to use typed events

EventEmitter is now a template class requiring a base event type, enforcing compile-time type safety for emitted events and listeners. Updated DisplayManager, KeyboardMonitor, Menu, MenuItem, TrayIcon, and WindowManager to inherit from EventEmitter with their respective event types. Refactored event classes (MenuEvent, TrayIconEvent, etc.) to provide a common base for related events. Removed the old untyped event_emitter.cpp implementation and updated platform-specific code to use typed events.

Author: lijy91

src/display_manager.h

@@ -35,7 +35,7 @@ namespace nativeapi {
  * Display primary = manager.GetPrimary();
  * @endcode
  */
-class DisplayManager : public EventEmitter {
+class DisplayManager : public EventEmitter<DisplayEvent> {
  public:
   /**
    * Get the singleton instance of DisplayManager