Improves all-day event rendering and handling

Refactors all-day event container handling to improve rendering and event delegation.

Ensures all-day containers are consistently created and managed,
preventing issues with event display and drag-and-drop functionality.

Moves event listener setup into dedicated methods for better
organization and reusability.

src/renderers/NavigationRenderer.ts

@@ -3,6 +3,8 @@ import { CoreEvents } from '../constants/CoreEvents';
 import { CalendarConfig } from '../core/CalendarConfig';
 import { DateCalculator } from '../utils/DateCalculator';
 import { EventRenderingService } from './EventRendererManager';
+import { CalendarTypeFactory } from '../factories/CalendarTypeFactory';
+import { eventBus } from '../core/EventBus';
 
 /**
  * NavigationRenderer - Handles DOM rendering for navigation containers
@@ -170,6 +172,13 @@ export class NavigationRenderer {
       
       header.appendChild(headerElement);
     });
+
+    // Always ensure all-day containers exist for all days
+    const headerRenderer = CalendarTypeFactory.getHeaderRenderer(this.config.getCalendarMode());
+    headerRenderer.ensureAllDayContainers(header as HTMLElement);
+    
+    // Add event delegation listener for drag & drop functionality
+    this.setupHeaderEventListener(header as HTMLElement);
     
     // Render day columns for target week
     dates.forEach(date => {
@@ -183,4 +192,38 @@ export class NavigationRenderer {
     });
   }
 
+  /**
+   * Setup event delegation listener for header mouseover (same logic as GridRenderer)
+   */
+  private setupHeaderEventListener(calendarHeader: HTMLElement): void {
+    calendarHeader.addEventListener('mouseover', (event) => {
+      const target = event.target as HTMLElement;
+      
+      // Check what was hovered - could be day-header OR all-day-container
+      const dayHeader = target.closest('swp-day-header');
+      const allDayContainer = target.closest('swp-allday-container');
+      
+      if (dayHeader || allDayContainer) {
+        const hoveredElement = dayHeader || allDayContainer;
+        const targetDate = (hoveredElement as HTMLElement).dataset.date;
+        
+        console.log('NavigationRenderer: Detected hover over:', {
+          elementType: dayHeader ? 'day-header' : 'all-day-container',
+          targetDate,
+          element: hoveredElement
+        });
+        
+        // Get the header renderer for addToAllDay functionality
+        const calendarType = this.config.getCalendarMode();
+        const headerRenderer = CalendarTypeFactory.getHeaderRenderer(calendarType);
+        
+        eventBus.emit('header:mouseover', { 
+          element: hoveredElement,
+          targetDate,
+          headerRenderer 
+        });
+      }
+    });
+  }
+
 }