Addresses PR #167 review (Hoshe H1/H2/H3, Tyre T2).
H1 — the VoxelCache 'same (seed, body_id, tile_pos) -> same column' invariant
is no longer unconditional after the T-1042 blend (the key omits blend_weight/
secondary). Replaced with an explicit precondition on the struct + get_or_derive:
the caller must pass the ChunkContext of the chunk that contains the tile.
H2/T2 — sec_phase claimed to be 'position-independent' but mixed in
primary_meander_phase/2 (the primary's per-position seed), making the secondary
phase proxy asymmetric and primary-contaminated. Dropped that term; sec_phase is
now the secondary's own morphology scalars (slope_q + moisture_q), with a comment
honestly naming it a bounded cosmetic approximation and where to thread the real
secondary seed if needed.
H3 — added cache_boundary_tile_blend_is_stable: derives a boundary ChunkContext
(blend_weight=128, secondary=Some), calls get_or_derive twice, asserts a cache
hit + identical blended elevation + that the Cow::Owned blend path actually ran.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
jpmschweitzerandClaude Opus 4.8
ff5e7ee944