Snap handle to opposite one

Summary:

When you drag a node handle, there should be an option to put it exactly opposite to other handle.

For example, snapping with Ctrl may snap it to opposite, like currently it snaps to existing.

Steps to reproduce:

1. Draw two curves connected with a cusp node.
2. How to make the node smooth if you may touch curve 2, w/o disturbing curve 1?
3. Same with Bézier/line tool (B). I stopped drawing for a while. I want to make the node smooth but greatly asymmetric…

My scenarios:

1. With flawed “Delete node” function (#8172 (moved)) I delete extraneous nodes, and manually try to fit the curve.
2. Font editing. I make something like “letter S with tail”. I get somewhere (or draw myself) both letter S and tail. And then I must graft them together, editing tail but not letter.

Sample attachments:

Version info

Inkscape 1.2.2 (732a01da63, 2022-12-09)

GLib version:     2.74.3
GTK version:      3.24.35
glibmm version:   2.66.5
gtkmm version:    3.24.7
libxml2 version:  2.10.3
libxslt version:  1.1.37
Cairo version:    1.17.7
Pango version:    1.50.12
HarfBuzz version: 5.3.1

OS version:       Windows 10 22H2