RayEdgeDistance returned double.MaxValue for touching vertices (dist ≈ 0),
causing rays from other vertices to hit the far side of stationary parts
and allow movement through obstacles. Now returns 0 when touching so the
distance > 0 check in PushSelected correctly prevents further movement.
Added directional edge filtering using outward normals to discard
back-facing edges before ray checks, reducing line count by ~2/3.
DirectionalDistance now checks both StartPoint and EndPoint per line
to preserve vertices at filtered edge boundaries.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
AJ Isaacs
08b31d0797