Cuttability analysis

Scans each piece for potential cutting hazards:

• Deep concavities – Detects narrow inward notches that could cause cracks.
• Sharp tips – Flags fragile convex points likely to chip.
• High concavity ratio – Identifies pieces whose area is much smaller than the convex hull, likely impossible to cut.
• Narrow necks – Measures local width along the piece and flags sections below safe glass-cutting thresholds.

The system applies sustained-violation filtering, arc-length-based sampling, and scoring to provide both warnings and errors, yielding a score per piece from 0 (impossible) to 1 (easy), and helps prioritize adjustments before cutting.