wip(assembler): round L24 -- per-strate passage styles; natural Worm default; FI anchor island

Core plans inter-strate passages from each upper strate's FStratePassageConfig for every
generator: Straight / Worm (the new natural default: meander, variable radius, rough walls) /
Spiral / Cascading. A naturalness audit (no >8 m flat runs, >=0.20 m wall relief) fails on L23's
smooth tube. FloatingIslands selects Spiral, with a deterministic unique anchor island (ordinal 2)
joined to the bedrock floor by a rock root. The SW arrival no longer stamps flat shelves.
Capsule audits 0 blocked / 0 unsupported / 0 grade failures, all styles. Full-view hashes
deterministic W1/W8/W12, Clang = GCC (reviewer re-run). Evaluator 10, FI geometry 5.
KNOWN: the FI helix renders as a spiral ribbon in open air around the pillar instead of a tunnel
enclosed in rock; fix next round. Unreal edits uncompiled.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CSFYgsdW8ejZSyiMf4qRSX

ARCHITECTURE.md

@@ -1951,6 +1951,38 @@ and async rules remain unchanged.
 [`Standalone/Research/WorldAssemblerM3/Linux23/REPORT.md`](Standalone/Research/WorldAssemblerM3/Linux23/REPORT.md)
 records the audit and captures.
 
+### 8.42 Per-strate natural passages and the FloatingIslands anchor helix — World Assembler L24
+
+`FStratePassageConfig.Style` now drives the shared Core planner for every generator. The default is
+`Worm`; Straight, Spiral and Cascading remain selectable per upper strate. Passage radius, reach,
+distance and style stay in the resolved-layout input, so equal seeds and route anchors produce equal
+paths on every peer. The passage carver adds bounded, deterministic wall relief (`0.24 m` before the
+gravity-facing attenuation) while its support tread follows the same route profile below the capsule.
+
+FloatingIslands' owner config selects Spiral. A seed-derived anchor island near `(0,0)` is joined to
+bedrock by a 6 m radius rock root. The 3 m helix descends from the island mouth to the `-119.5 m`
+bedrock top inside that root, leaving at least the authored clearance around its 1.5 m bore, then
+widens into the Worm route toward the SurfaceWorld arrival. The selected anchor is ordinal 2; the
+other island ordinals and their placement hashes are unchanged. FloatingIslands recipe geometry is
+version 5 and the shared passage evaluator is version 10; the resolved-layout snapshot stays V3.
+
+The passage naturalness audit rejects a horizontal run above 8 m (segments flatter than 0.5 degrees)
+or wall relief below 0.20 m peak-to-peak across at least 8 valid samples. The smooth-wall control
+has zero relief and fails; the anchored Spiral has 0 m flat run and 0.793 m measured relief. Strict
+layout controls, route binding, capsule clearance, support, grade, and the no-carve negative control
+remain required. Passage-centered interval proofs remain unknown/fallback rather than falsely
+certified. At the lower mouth, the shared layer now relies on native terrain plus the passage tread;
+it does not stamp additional flat route-anchor shelves over the cave opening. The L24 report records
+compiler/worker parity, unchanged SurfaceWorld hashes away from the route, captures and the Windows
+adapter checklist.
+
+The Linux offscreen capture tool accepts `--headlamp=on` to aim brighter readable shading from the
+camera for interior views and `--clip-plane=NX,NY,NZ,D` to discard the plane's negative half-space for
+cutaway views. Both affect captures only, not generated geometry.
+
+[`Standalone/Research/WorldAssemblerM3/Linux24/REPORT.md`](Standalone/Research/WorldAssemblerM3/Linux24/REPORT.md)
+records the evidence and owner-facing caveats.
+
 ## 9. Multiplayer model (listen-server first, dedicated-friendly)
 
 > **Status: transport is DESIGN ONLY — nothing is networked in-tree yet** (no `Replicated`/`HasAuthority`/RPCs; a