[Feature Request] Expanding on #91 to allow dragging the root node from the TabFern GUI panel to an external app

I'm requesting a feature that is native to the closed source Tabs Outliner and is one I use all the time.
It is an expansion of [Issue #91](https://github.com/cxw42/TabFern/issues/91)
I would like to left-click and drag the top-level "node" or top hierarchy of a set of sub-tabs out of the TabFern GUI panel into an external application.
More specifically I would like to drag the top-level "node" into a Word or OneNote document.
The "dropped" set of tabs show in the external application as a list of webpage titles with embedded links without showing visible URL addresses.
**For reference:**
This native feature of Tabs Outliner is also achievable by highlighting a OneTab group list and either cut and pasting or drag and dropping into an external application.
Either highlighting and copying or drag and dropping a TabFern GUI panel tab list (with imbedded URLs) is fine. Whichever is easier to code .
Other than this missing feature, the TabFern extension is brilliant!

Start by reading Issue #91 and the TabFern GUI panel's existing tab-list interaction behavior. Determine whether copying or dragging is the clearer entry point for exporting a top-level node and its child tabs to an external application. Done means an exported group appears as webpage titles with embedded links and no visible URL addresses.

Written by the indexing model from the issue text.