Addresses the Hoshe (QA) + Tyre (architecture) review of the SeedChain/cascade
work:
- Golden was pinning an empty river network (128x64 produced 0 river cells).
Bumped to 256x128, where GJ1c yields a real network (93 river cells, 19
mouths) — Layer 1's rivers are now actually guarded, not just attractors.
- SeedChain::for_body(world_seed, body_id) + fnv1a_64: the single canonical
body_id(String) -> u64 path (FNV-1a, the repo convention), so callers can't
derive divergent worlds from the same seed via different ad-hoc hashes. The
golden now uses it.
- Stability guards: seed_domain_discriminants_are_pinned test (CI fails if a
SeedDomain tag is renumbered); AttractorType gains #[repr(u8)] + explicit
discriminants (it's cast as a sort key in features.rs).
- Tests: SeedChain::root(0) non-degenerate; run_cascade error path (missing
file -> Err, not panic).
- Comments: clarified the id=0 derivations (sibling separation is caller-side
via the per-district/quarter chain; #957 threads the index), tightened the
all_district_types reachability comment (it pins the seed-0 sequence, not a
probabilistic claim), and noted the golden's WORLD_SEED is cosmetic at
Layers 0-1 + the x86_64 f32 capture caveat.
Deferred with reason: the run_cascade -> CascadeInputs struct refactor (Tyre)
is left for #954 — designing Layer-2's context shape now would be later-phase
detail, and there's a single caller to migrate then. EntityRng keeps its
domainless combine (migrating is stream-changing) — noted in D-224.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
jpmschweitzerandClaude Opus 4.7
a61d030b47