wip(assembler): M1 round 5 -- native SurfaceWorld manifest delivered into the Unreal Core route

Manifest imported into UVoxelSettings (hash 8933693d9560ba9f), folded into the season
content hash only when Core is on. BuildHost: W1/W8/W16 stable, 2553 surface tiles match
standalone, 432 LOD transitions, collision on all 36 expected tiles. Matched timing
96.8 s native vs 197.3 s bridge (2.04x). Collision support tiles wait for Core region admission.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ

Source/VoxelForge/Private/VoxelWorld.cpp

@@ -40,6 +40,7 @@
 #include "Engine/World.h"
 #include "Misc/IQueuedWork.h"
 #include "Misc/QueuedThreadPool.h"
+#include "Misc/SecureHash.h"
 #include "RealtimeMeshCollisionLibrary.h"
 #include "Camera/PlayerCameraManager.h"
 #include "Async/Async.h"
@@ -7259,6 +7260,15 @@ bool AVoxelWorld::InitializeVoxelForgeCoreWorld()
             UTF8_TO_TCHAR(CoreError.c_str()));
         return false;
     }
+    if (const VoxelForgeCore::WorldAssemblyManifest* Assembly = Snapshot->worldAssembly())
+    {
+        UE_LOG(LogTemp, Display,
+            TEXT("[VoxelForgeCoreRuntime] world_assembly_hash=%016llx recipe_hash=%016llx plan_hash=%016llx strates=%d"),
+            static_cast<unsigned long long>(Assembly->contentHash),
+            static_cast<unsigned long long>(Assembly->recipe.contentHash),
+            static_cast<unsigned long long>(Assembly->plan.contentHash),
+            static_cast<int32>(Assembly->plan.strates.size()));
+    }
 
     TSharedPtr<FVoxelForgeCoreRuntimeState, ESPMode::ThreadSafe> State =
         MakeShared<FVoxelForgeCoreRuntimeState, ESPMode::ThreadSafe>();
@@ -7786,6 +7796,18 @@ void AVoxelWorld::RequestCollisionGateSupportTile(const FVoxelTileKey& SupportTi
     }
     bForceDesiredRebuild |= bNeedsDesiredRebuild;
 
+    // Core surface tiles must enter through the desired-set region compile before collision work.
+    // Les tuiles de surface Core doivent passer par la compilation de région avant la collision.
+    if (bUseVoxelForgeCore && !bDesiredAtRequest)
+    {
+        UE_LOG(LogTemp, Display,
+            TEXT("[VoxelForgeCollisionGate] support_request_deferred tile=(%d,%d,%d) "
+                 "reason=core_region_admission desired=0"),
+            SupportTile.Coord.X, SupportTile.Coord.Y, SupportTile.Coord.Z);
+        bPawnGateSupportRequestReported = true;
+        return;
+    }
+
     // Preserve the established critical floor ordering when it already belongs to this desired
     // epoch. Before the first build there is no array to promote into; LoadTile below still uses
     // the same CollisionCritical work class and priority queue.
@@ -13222,7 +13244,47 @@ int32 AVoxelWorld::GetCurrentSeason() const
 
 FString AVoxelWorld::GetCurrentSeasonContentHash() const
 {
-    return StrateManager ? StrateManager->GetSeasonContentHash() : FString();
+    const FString SeasonHash = StrateManager ? StrateManager->GetSeasonContentHash() : FString();
+    // Only active Core generation includes the optional native surface manifest in world identity.
+    // Seul le Core actif inclut le manifeste de surface natif dans l'identite du monde.
+    if (!Settings || !bUseVoxelForgeCore)
+    {
+        return SeasonHash;
+    }
+
+    FString AssemblyJson;
+    FString AssemblyHash;
+    FString AssemblyError;
+    if (!Settings->GetWorldAssemblyManifestJson(AssemblyJson, AssemblyHash, AssemblyError))
+    {
+        return FString();
+    }
+    if (AssemblyHash.IsEmpty())
+    {
+        return SeasonHash;
+    }
+
+    FString Payload = SeasonHash;
+    if (Payload.IsEmpty())
+    {
+        Payload = FString::Printf(TEXT("seed=%d"), StrateManager ? StrateManager->GetWorldSeed()
+                                                                : Settings->GetEffectiveWorldSeed());
+        if (StrateManager)
+        {
+            for (const FStrateSlot& Slot : StrateManager->GetLayout())
+            {
+                Payload += FString::Printf(TEXT("|strate=%d,%d,%d,%s"), Slot.StrateIndex,
+                    Slot.TopChunkZ, Slot.BottomChunkZ,
+                    Slot.Definition ? *Slot.Definition->GetPathName() : TEXT("missing"));
+            }
+        }
+    }
+    Payload += TEXT("|world_assembly=");
+    Payload += AssemblyHash;
+    FTCHARToUTF8 Utf8Payload(*Payload);
+    uint8 Digest[FSHA1::DigestSize];
+    FSHA1::HashBuffer(Utf8Payload.Get(), Utf8Payload.Length(), Digest);
+    return BytesToHex(Digest, FSHA1::DigestSize);
 }
 
 //=============================================================================