wip(assembler): round L22 -- one 8 m layout chunk for every strate; real ceiling -> content -> bedrock

StrateLayoutChunkSizeMeters (world setting, default 8 m; owner decision) is resolved once in
the director/adapter and standalone loader; every generator reads the resolved width (no
CHUNK_SIZE / Core-tile inference). Every strate gets solid ceiling and bedrock bands from its
BoundarySealThickness in the shared composition path (diggable by default); faces come from the
shared boundary path. Owner world: FloatingIslands +8..-120 m (128 m, now with a bedrock floor),
SurfaceWorld -120..-632 m (unchanged; full-detail and exact-query hashes equal L21); the 60 m gap is
gone. The strict layout validator passes on the real world, with 0 endpoint dispatch
disagreements. Spawn/benchmark camera derived from route.front. Ledges under the islands gone
(reviewer capture). Evaluator 7, recipe schema 2, layout snapshot 2, FI geometry 4.
Open: SW cap profiles exceed the ceiling band (owner call); transitions still Hard; Unreal
setting/manager/adapter edits uncompiled here.

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

CLAUDE.md

@@ -26,9 +26,12 @@ try to run anything.
 - **Density sign: negative = solid, positive = air** (MC convention at the mesher).
   `FVoxelModification::Strength` negative = carve. *The #1 source of confusion.*
 - **Density functions take VOXEL coords, not cm.** The legacy plugin field uses 12.5 cm voxels;
-  the opt-in Core field uses 25 cm voxels and its own tile keys. One legacy 32³ chunk is 4 m.
-  Conversions live in `VoxelTypes.h` and the Core bridge; do not mix scales in queries, anchors, edits,
-  or surface lookups.
+  the opt-in Core field uses 25 cm voxels and its own 32³-voxel storage tile. The legacy 32³ chunk
+  spans 4 m at 12.5 cm. Strate placement uses the separate world-level `StrateLayoutChunkSizeMeters`
+  setting (8 m by default), resolved once and shared by every generator. At 25 cm that layout unit is
+  32 Core voxels; at 20 cm it is 40. Never infer the layout unit from `CHUNK_SIZE` or the Core tile.
+  Conversions live in `VoxelTypes.h`, the director, and the Core bridge; do not mix scales in queries,
+  anchors, edits, or surface lookups.
 - **Determinism:** all randomness = hash of (coord, seed, strateIndex). No RNG state — same seed ⇒
   same world. Player edits (diff layer) are the only non-deterministic overlay.
 - **Core world invariants:** Core density keeps the same sign (negative solid, positive air), but Core