Updates navigation event data

Updates the navigation event to include the current date
instead of the week start.

Makes the target date optional when rendering an all-day event.

src/renderers/AllDayEventRenderer.ts

@@ -63,7 +63,7 @@ export class AllDayEventRenderer {
   /**
    * Render an all-day event using factory pattern
    */
-  public renderAllDayEvent(event: CalendarEvent, targetDate: string): HTMLElement | null {
+  public renderAllDayEvent(event: CalendarEvent, targetDate?: string): HTMLElement | null {
     const container = this.getContainer();
     if (!container) return null;