Backend: - Set POLYLINE edge routing on ELK root — eliminates curved/bent edges between horizontally aligned nodes - Collect edges from handler section roots (not just main root) so internal handler edges are included in the layout output - Use correct root reference for coordinate calculation per edge Frontend: - Render ALL edge points as line segments (polylines), not cubic bezier. ELK bend points are waypoints, not bezier control points — the cubic bezier interpretation caused false curves. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>