- Pion (Pawn): orthogonal range 1, social status 1 (lowest), green color
- All existing levels get surplus stock including pawns for player choice
- Level 4 "Le Carrefour": 8x8, dual cargo diagonal routes, center wall block
- Level 5 "Le Labyrinthe": 8x6, wall corridors, knights essential for shortcuts
- Level 6 "Trois Royaumes": 10x8, 3 productions + 3 demands, full network puzzle
- Production interval concept removed (all produce every turn)
- GDD updated with Pion section and 6 level descriptions
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- Fix cargo bouncing in relay chains: piece-to-piece transfers now prefer
receivers farther from production (forward flow) instead of closer (backward)
- Level 2 stock corrected: 4R+1B → 6R+1B to match required solution
- Level 3 simplified to single cargo type (6R+1K) — dual-cargo on 6x6
requires engine support for cargo-type filtering (Phase 2)
- Add PLAN.md with prototype roadmap (phases 2-6)
- 57 tests passing
