Refactor calendar datasource architecture

Centralizes date calculation logic into DateColumnDataSource
Improves separation of concerns across rendering components

Key changes:
- Introduces IColumnInfo interface for flexible column data
- Moves date calculation from multiple managers to dedicated datasource
- Removes duplicate date rendering logic
- Prepares architecture for future resource-based views

src/datasources/DateColumnDataSource.ts

@@ -1,4 +1,4 @@
-import { IColumnDataSource } from '../types/ColumnDataSource';
+import { IColumnDataSource, IColumnInfo } from '../types/ColumnDataSource';
 import { DateService } from '../utils/DateService';
 import { Configuration } from '../configurations/CalendarConfig';
 import { CalendarView } from '../types/CalendarTypes';
@@ -32,17 +32,28 @@ export class DateColumnDataSource implements IColumnDataSource {
   /**
    * Get columns (dates) to display
    */
-  public getColumns(): Date[] {
+  public getColumns(): IColumnInfo[] {
+    let dates: Date[];
+
     switch (this.currentView) {
       case 'week':
-        return this.getWeekDates();
+        dates = this.getWeekDates();
+        break;
       case 'month':
-        return this.getMonthDates();
+        dates = this.getMonthDates();
+        break;
       case 'day':
-        return [this.currentDate];
+        dates = [this.currentDate];
+        break;
       default:
-        return this.getWeekDates();
+        dates = this.getWeekDates();
     }
+
+    // Convert Date[] to IColumnInfo[]
+    return dates.map(date => ({
+      identifier: this.dateService.formatISODate(date),
+      data: date
+    }));
   }
 
   /**