wip(assembler): round L29 -- strate transitions honoured at the bedrock/ceiling interface

EVoxelStrateTransition from the upper strate shapes the bedrock(N)/ceiling(N+1) interface in the
shared composition layer: Hard flat; Gradient = smooth 2D hash surface (16 m owner width, about 4 m
measured undulation); Interleaved = 3D domain-warped fingered overlap within the width. Each band
keeps >= 2 Core voxels solid; faces return to the seam near passage mouths. Interface audit over
512 m: 0 hole columns for all modes; wider-than-declared and too-thin controls rejected. All passage,
route, proof and validator audits pass; deterministic Clang = GCC. Evaluator 15. Cost +4% SW,
+1.3% FI vs L28. Open: ring-like artifact on the FI floor capture; transition look unverified.

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

ARCHITECTURE.md

@@ -1883,8 +1883,9 @@ Each record separates the nominal ceiling, content, and bedrock bands. A strict
 sequence for every strate and requires bedrock(N) to touch the next strate's ceiling(N+1). The two
 bands remain separately owned. Gradient and Interleaved interfaces may declare interpenetration only
 inside their explicit transition zone; Hard has zero effective width. The manager's `TransitionBlendChunks`
-is expressed in owner-chunk metres. Interleaved's existing two-chunk domain warp extends its possible
-fingers beyond the blend width and is recorded separately. Compatibility validation reports current
+is expressed in owner-chunk metres. L21 recorded the older Interleaved allowance as blend width plus
+warp amplitude; L29 now treats the declared blend width as the complete physical crossing allowance.
+Domain warp changes finger placement, but cannot extend overlap beyond that width. Compatibility validation reports current
 gaps, overlaps, ambiguities, inactive/missing bands, and unhonoured transitions while accepting them;
 strict validation rejects them. Core dispatches per-strate recipe fields without applying that
 parameter blend, even though the legacy manager helper implements it. Both band types default diggable,
@@ -1943,6 +1944,7 @@ opens a band; the support strip stays below the player capsule. The lower mouth
 monotone descent from the short route-bound landing tail, whose height may vary with the route.
 Both route and passage audits sample the 0.34 m by 1.76 m capsule, support probes, and grade; the
 negative control compiles the same world without passage carving and must detect a blocked capsule.
+
 The L23 shared-field change is `WorldAssemblyEvaluatorVersion=9`. It does not change the L22 bands
 or any generator's field away from a passage. The L23 report includes exact-query/hash comparisons,
 the blocked control, captures, and the Windows adapter checklist. §8.10's cache, proof, streaming,
@@ -2051,6 +2053,29 @@ proof bounds preserve the L27 output.
 [Linux28 report](Standalone/Research/WorldAssemblerM3/Linux28/REPORT.md)
 records counts, parity, costs and audit caveats.
 
+### 8.46 Honored bedrock/ceiling transitions — World Assembler L29
+
+The upper strate's `EVoxelStrateTransition` controls the shared interface between its bedrock band
+and the next strate's ceiling band in the Core composition path. `TransitionBlendChunks` is converted
+using the resolved layout chunk width (8 m by default). Hard preserves the flat interface. Gradient
+moves the shared surface with a smooth 2D hash field whose peak-to-peak range is at most one quarter
+of the declared width. Interleaved uses a seed/interface/coordinate-keyed, domain-warped 3D hash field
+to set actual overlap between the facing bands from zero to the declared width. The two faces move
+inward by half that overlap; the warp changes finger placement without increasing the crossing
+allowance. Both bands keep authored thickness, and their solid intervals touch or overlap in every
+XY column. Core does not blend unrelated generator fields.
+
+Each boundary band keeps at least **two Core voxels** of solid thickness (0.5 m at the default 25 cm
+voxel size). Strict validation rejects thinner bands and declared interpenetration beyond the
+transition width. The world audit samples a 512 m square XY area, measures actual crossing depth and
+minimum band thickness, and sweeps every non-passage column through both bands at half-voxel spacing.
+Passage columns are excluded from the hole sweep. Near an interface mouth, the shared face returns to
+its nominal height inside the mouth radius plus a 1 m support margin, then fades back to the selected
+transition over 2 m so the authored landing floor remains supported. Negative controls reject a
+transition one micrometre wider than declared and a band one micrometre below the minimum. See
+[`Standalone/Research/WorldAssemblerM3/Linux29/REPORT.md`](Standalone/Research/WorldAssemblerM3/Linux29/REPORT.md)
+for audit measurements, hashes, timings, captures and run history.
+
 ## 9. Multiplayer model (listen-server first, dedicated-friendly)
 
 > **Status: transport is DESIGN ONLY — nothing is networked in-tree yet** (no `Replicated`/`HasAuthority`/RPCs; a