Improves all-day event layout and drag behavior

Refactors all-day event layout calculation and rendering for improved accuracy and performance.

Improves drag-and-drop behavior for all-day events, ensuring correct event placement and column detection.

Addresses issues with event overflow display and provides a more responsive user experience.

src/utils/ColumnDetectionUtils.ts

@@ -83,17 +83,8 @@ export class ColumnDetectionUtils {
         return column || null;
     }
 
-    /**
-     * Clear cache (useful for testing or when DOM structure changes)
-     */
-    public static clearCache(): void {
-        this.columnBoundsCache = [];
-    }
-
-    /**
-     * Get current cache for debugging
-     */
-    public static getCache(): ColumnBounds[] {
+  
+    public static getColumns(): ColumnBounds[] {
         return [...this.columnBoundsCache];
     }
 }