- Split collision.ts (707→549): extract distance.ts (pure math) and grid-snap.ts
- Fix curved conveyor/chute outline to match SVG viewBox geometry
- Draw curves programmatically with fixed 30px band width (no SVG stretching)
- Single resize handle for curves (was 2)
- Add .gitattributes for consistent line endings
- Make Vec2 type module-private
- Add mirror transform support in renderer
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>