Feature Request: Dual Pane Support for Better Productivity

[smlabor-sketch]

Subject: Feature Request: Dual Pane Support for Better Productivity

Description:
First of all, thank you for creating such a lightweight and high-performance file explorer. As a heavy user who handles a vast amount of administrative documents daily, I find Explorer++'s speed to be unparalleled.

However, the lack of a "Dual Pane (Split View)" feature is the only thing holding me back from using it as my primary tool. Having two directories open side-by-side with their respective tree panes would significantly improve the efficiency of file comparison and organization.

Request:
Could you please consider adding a vertical/horizontal split-view option? This would make Explorer++ the absolute "commander-style" king of lightweight explorers.

Thank you for your hard work and dedication to this project!