React Flow's selection changes had nowhere to go: the canvas passed
edges but no onEdgesChange, so no edge ever carried .selected and both
the selected-edge stroke and its rest colour were unreachable. The edges
are derived from the bindings, so the selected ids are held on their own
and marked on after the layout has had the array — a rebuild cannot drop
the selection, and selecting cannot make the graph lay itself out again.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SKL7sUgNWhukDEz95vSMQv