Import each subfolder from putty portable settings folder

[Roman]

Is your feature request related to a problem? Please describe.
There is a feature Import Sessions > from putty portable settings but it never imports subfolders of selected folder.
For now user needs to import each subfolder manually, and sessions from imported subfolders aren't grouped into subfolders in SP's tree.

Describe the solution you'd like
Option to import all subfolders from selected folder and keep grouping of sessions as in imported folder and its subfolders.

Additional context
I am using superputty with combination of kitty portable.