Add Drag-and-Drop Support for Folders

[PleasureOverMatter]

Description
It would be super helpful to have drag-and-drop support for folders in Screenbox. Instead of adding files one by one, we could just drag a whole folder in, and Screenbox would load everything inside, including files in subfolders.

Details

• Functionality: Drag a folder into Screenbox, and it auto-imports all the files inside, including subfolder contents.
• Expected Behavior: Keep folder structure if possible, and handle nested folders if they're there.
• Error Handling: If there are unsupported files, show a quick notification or skip them.

Thanks for considering this feature!