Description of the new feature/enhancement

The current way of splitting panes using written commands or shortcuts is awesome but difficult to discover.
There is already some drag & drop support for reordering tabs. It would be awesome to be able to drag & drop a tab to split a pane in the previous tab. An exemple of user interaction sequence:

• Open Windows terminal: it shows a single tab with a single pane with powershell
• Hit ctrl+shift+3 to open a ubuntu tab
• drag the ubuntu tab > it shows me the previous tab (powershell)
• using my mouse I can move the ubuntu tab into sensitive zones an preview the resulting split (a bit like Visual Studio/code UI)
• I can then drop, and get a nice splitted pane.

Optionally, show a popup saying "Want to automate that ? click here to copy an automation script to your clipboard", which would copy a script that would do the same thing.

Proposed technical implementation details (optional)

Well, I am sure it is possible to do that by writing some code :)