Fuzzes procgen through its standardized data-container interface: direct
HeightMap and DiscreteMap operations (scalar, binary, bitwise, subscript)
plus one-directional conversions NoiseSource.sample -> HeightMap,
BSP.to_heightmap, DiscreteMap.from_heightmap, and dm.to_heightmap.
Treating HM/DM as the unified surface covers every procgen system
without fuzzing each individually.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
