CV Mesh Vertex Normals

Turns a MESH (vertices + triangles) into the Nx6 (x,y,z,nx,ny,nz) cloud 'CV PPF Pose Estimation' and 'CV ICP Register' want, with the normals taken from the TRIANGLE WINDING - so they point consistently outward instead of being sign-arbitrary. Use this, not 'CV Point Cloud Normals', whenever the cloud comes from a mesh: a plane fit through k neighbours cannot tell inside from outside, and on a closed model matched against a single-view scene that ambiguity puts the PPF pose ~180 degrees out (measured 177-179 on the shipped example, against 9.2 with these normals). Each vertex gets the AREA-WEIGHTED sum of its incident face normals, so large triangles dominate the average as they should. Wire it AFTER 'CV Mesh Split Long Edges' - that node adds vertices, and normals must follow the final topology. Failure tolerant: an empty mesh or an index out of range returns empty arrays with found=false.