vim: keyboard (vim) binding to scroll the LSP hover

[lucascherzer]

Check for existing issues

• Completed

Describe the feature

In my vim config, pressing K twice while hovering over a code element focuses the documentation pane that appears when pressing Kthe first time in vim mode. From then on, vim motions do not refer to the source code file anymore, but instead they are applied to the documentation pane.
Of course, the buffer is not editable and this can be exited with :q or perhaps using Esc

If applicable, add mockups / screenshots to help present your vision of the feature

https://asciinema.org/a/iUyR5IFa292GYjQpSlZSbnIqR

[ConradIrwin]

Duplicate of #7284