Updates the `HeaderManager` to utilize `mouseenter` and `mouseleave` events on the calendar header for improved performance and accuracy.
Calculates the target date based on the mouse's X-coordinate within the header.
Removes the need for 'ghost columns' by simplifying the logic. This significantly reduces complexity.
The `AllDayEventRenderer` is modified to reflect this change, omitting ghost column creation.
Updates `DragDropManager` to accommodate the new interaction model.
Various console logs are added for debugging purposes.
