Refactor calendar datasource and event management

Enhances calendar flexibility by introducing group-based column spanning and improving cross-mode event handling

Adds support for:
- Dynamic column grouping in date and resource modes
- Consistent event drag-and-drop across different calendar views
- More robust all-day event layout calculations

Improves event management logic to handle resource and date mode transitions more elegantly

src/renderers/ResourceColumnRenderer.ts

@@ -1,5 +1,6 @@
 import { WorkHoursManager } from '../managers/WorkHoursManager';
 import { IColumnRenderer, IColumnRenderContext } from './ColumnRenderer';
+import { DateService } from '../utils/DateService';
 
 /**
  * Resource-based column renderer
@@ -10,13 +11,19 @@ import { IColumnRenderer, IColumnRenderContext } from './ColumnRenderer';
  */
 export class ResourceColumnRenderer implements IColumnRenderer {
   private workHoursManager: WorkHoursManager;
+  private dateService: DateService;
 
-  constructor(workHoursManager: WorkHoursManager) {
+  constructor(workHoursManager: WorkHoursManager, dateService: DateService) {
     this.workHoursManager = workHoursManager;
+    this.dateService = dateService;
   }
 
   render(columnContainer: HTMLElement, context: IColumnRenderContext): void {
-    const { columns } = context;
+    const { columns, currentDate } = context;
+
+    if (!currentDate) {
+      throw new Error('ResourceColumnRenderer requires currentDate in context');
+    }
 
     // Hardcoded work hours for all resources: 09:00 - 18:00
     const workHours = { start: 9, end: 18 };
@@ -25,6 +32,7 @@ export class ResourceColumnRenderer implements IColumnRenderer {
       const column = document.createElement('swp-day-column');
 
       column.dataset.columnId = columnInfo.identifier;
+      column.dataset.date = this.dateService.formatISODate(currentDate);
 
       // Apply hardcoded work hours to all resource columns
       this.applyWorkHoursToColumn(column, workHours);