Tab in a mind map topic being rewritten keeps the words and hands focus
back to the map; it asks for no child while the field is open, and the
map's keys wait for the field. Tests cover a new wire into a wired input
replacing the old, a connector released on its own shape linking
nothing, and a deleted whiteboard shape taking its links with it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>