Adds event resize handle mouse enter tracking

Implements mouse enter event listener on calendar container to log resize handle visibility for debugging

Enhances event resize handle interaction tracking

src/managers/ResizeHandleManager.ts

@@ -81,11 +81,29 @@ export class ResizeHandleManager {
   }
 
   private attachGlobalListeners(): void {
+    const calendarContainer = document.querySelector('swp-calendar-container');
+    
+    if (calendarContainer) {
+      calendarContainer.addEventListener('mouseenter', this.onMouseEnter, true);
+    }
+
     document.addEventListener('pointerdown', this.onPointerDown, true);
     document.addEventListener('pointermove', this.onPointerMove, true);
     document.addEventListener('pointerup', this.onPointerUp, true);
   }
 
+  private onMouseEnter = (e: Event): void => {
+    const target = e.target as HTMLElement;
+    const eventElement = target.closest<SwpEventEl>('swp-event');
+    
+    if (eventElement) {
+      const handle = eventElement.querySelector('swp-resize-handle');
+      if (handle) {
+        console.log('Resize handle visible on event:', eventElement.dataset.eventId);
+      }
+    }
+  };
+
   private subscribeToEventBus(): void {
     const eventsToRefresh = [
       CoreEvents.GRID_RENDERED,