Optimizes the drag-and-drop `mousemove` event handler by caching the previously hovered element. The `drag-over` class is now only removed from `prevOver` and added to the new hover target, instead of looping through all `cachedItems` to remove the class on every move. This eliminates layout thrashing and high CPU usage during drag operations.
Co-authored-by: Horizontal42 <75383519+Horizontal42@users.noreply.github.com>
