mazes!

[bobnik]

Adds a new Maze shape that generates drawable mazes for sand tables. Supports four grid types and seven algorithms, with continuous path drawing via Chinese Postman algorithm.

Grid types:

• Rectangle - traditional cartesian grid
• Circle (Polar) - concentric rings with configurable wedge doubling
• Hexagon - pointy-top hex grid
• Triangle - delta grid with alternating triangles

Algorithms:

• Wilson, Backtracker, Prim, Kruskal (all grid types)
• Division, Sidewinder, Eller (rectangle only)

Drawing options:

• Show entry/exit arrows (finds hardest path through maze)
• Show solution path (spline-smoothed)
• Circle mazes: segment or arc walls
• Algorithm-specific tweaks: straightness, horizontal bias, branch level

Technical highlights:

• Unified grid abstraction layer for algorithm portability
• Chinese Postman + Eulerian trail for continuous single-path drawing

Attribution:

• codebox/mazes by Rob Dawson (MIT) - polar/hex/triangle grid implementations
• Jamis Buck's maze algorithms (CC BY-NC-SA 4.0) - Wilson's algorithm reference
• See src/features/shapes/maze/LICENSE for full details

Test plan

• [ ] Verify all 4 grid types render correctly
• [ ] Test each algorithm on its supported grid types
• [ ] Verify entry/exit arrows display and connect properly
• [ ] Test solution path rendering with arrows
• [ ] Confirm seed produces reproducible results
• [ ] Test dimension changes update transformer proportionally