proto: first liminal fixtures - flat field + monolith, periodic hills, raised road in fog (L141)

Standalone only: fixtures, liminal_road_override (fillDais), --audit-liminal-road-walk, capture-only distance fog.
Road 65 m x 6 m, 22 m up, capsule walk 127/127. Owner hashes unchanged (v227), fast tier, Clang/GCC green.
Hills repeat every 80 m but the capture reaches 56 m, so only one rise shows. Also R48 (who owns the tunnel mouth):
recommends a bounded joint plan of passage ports and layer landing candidates.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016dhxM43dnWvUu2B5Ph1iG1

Standalone/Source/StreamBenchmarkPipeline.h

@@ -2384,7 +2384,8 @@ namespace StandaloneStreamBenchmark
         bool bMovingCameraTrace=false,double MovingCameraSpeedMetersPerSecond=0.0,
         double MovingCameraDurationSeconds=12.0,double MovingCameraDwellSeconds=5.0,
         bool bColdWorkerTimeline=false,bool bAuditPassageSourceClamp=false,
-        bool bAuditPassageCarveReach=false,bool bAuditPassageTileSeams=false)
+        bool bAuditPassageCarveReach=false,bool bAuditPassageTileSeams=false,
+        bool bAuditLiminalRoadWalk=false)
     {
         using Clock=std::chrono::steady_clock;
         const std::clock_t ColdCpuOrigin=std::clock();
@@ -2554,7 +2555,7 @@ namespace StandaloneStreamBenchmark
             ||bAuditOreVeinYield||bAuditLandmarkReachability||bAuditStrateTransitions
             ||bAuditResolvedLayoutPassages||bAuditResolvedLayoutBoundaries
             ||bAuditTileShapeReadiness||bAuditBasePageEquivalence||bAuditRouteParity
-            ||bAuditPassageSourceClamp||bAuditPassageCarveReach;
+            ||bAuditPassageSourceClamp||bAuditPassageCarveReach||bAuditLiminalRoadWalk;
         const bool bDeferFarWorld=bIncludeFarWorld&&!bMovingCameraTrace&&!bFarWorldAudit;
         VoxelForgeCore::ShapeBuildRequest ShapeRequest;
         ShapeRequest.minVoxel={FineMin.X,FineMin.Y,FineMin.Z};
@@ -2820,10 +2821,10 @@ namespace StandaloneStreamBenchmark
             Streamer.Stop();
             return passed?0:11;
         }
-        if(bAuditResolvedLayoutPassages)
+        if(bAuditResolvedLayoutPassages||bAuditLiminalRoadWalk)
         {
             if(ResolvedLayout==nullptr||!CoreSnapshot.resolvedLayout())
-            {Streamer.Stop();std::fprintf(stderr,"[ResolvedPassageAudit] missing resolved-layout snapshot\n");return 2;}
+            {Streamer.Stop();std::fprintf(stderr,"[ResolvedWalkAudit] missing resolved-layout snapshot\n");return 2;}
             struct FWalkAudit
             {
                 std::uint64_t segments=0,centers=0,capsuleSamples=0,blocked=0;
@@ -2961,6 +2962,67 @@ namespace StandaloneStreamBenchmark
                     &&audit.gradeFailures==0;
                 return audit;
             };
+            const auto auditLiminalRoadWalk=[&](bool required)
+            {
+                bool found=false;
+                bool passed=true;
+                for(const auto& road:ResolvedLayout->stamps)
+                {
+                    if(road.stableId!="liminal/raised-road-v1")continue;
+                    found=true;
+                    const bool longAxisX=(road.yawQuarterTurns&1u)==0;
+                    const double centerX=road.positionMicrometres[0]/1.0e6;
+                    const double centerY=road.positionMicrometres[1]/1.0e6;
+                    const double centerZ=road.positionMicrometres[2]/1.0e6;
+                    const double halfLength=road.halfExtentsMicrometres[longAxisX?0:1]/1.0e6;
+                    const double halfWidth=road.halfExtentsMicrometres[longAxisX?1:0]/1.0e6;
+                    const double deckZ=centerZ+road.halfExtentsMicrometres[2]/1.0e6;
+                    constexpr double CapsuleRadiusMetres=0.34;
+                    constexpr double CapsuleHeightMetres=1.76;
+                    constexpr double HalfCapsuleHeightMetres=CapsuleHeightMetres*0.5;
+                    constexpr double EndInsetMetres=1.0;
+                    std::vector<std::array<double,3>> roadPath;
+                    const double inset=std::min(EndInsetMetres,halfLength*0.25);
+                    for(const double along:{-halfLength+inset,halfLength-inset})
+                        roadPath.push_back({(centerX+(longAxisX?along:0.0))/coreMetres,
+                            (centerY+(longAxisX?0.0:along))/coreMetres,
+                            (deckZ+HalfCapsuleHeightMetres)/coreMetres});
+                    const FWalkAudit roadAudit=auditPlayerPath(Shape,roadPath,
+                        0.125,0.125,1.125,3,0.45);
+                    const double widthMetres=2.0*halfWidth;
+                    const double horizontal=std::hypot(roadPath[1][0]-roadPath[0][0],
+                        roadPath[1][1]-roadPath[0][1])*coreMetres;
+                    const double vertical=std::abs(roadPath[1][2]-roadPath[0][2])*coreMetres;
+                    const double gradeDegrees=std::atan2(vertical,horizontal)*
+                        57.29577951308232;
+                    passed=road.kind==VoxelForgeCore::ResolvedSdfStampKindV1::fillDais
+                        &&widthMetres>=2.0*CapsuleRadiusMetres
+                        &&gradeDegrees<=15.0&&roadAudit.passed;
+                    std::printf("[LiminalRoadWalkAudit] id=%s stations=%llu capsule_samples=%llu "
+                        "blocked=%llu support_samples=%llu unsupported=%llu grade_failures=%llu "
+                        "width_m=%.3f capsule_diameter_m=%.3f grade_deg=%.3f grade_limit_deg=15.000 "
+                        "status=%s\n",road.stableId.c_str(),
+                        static_cast<unsigned long long>(roadAudit.centers),
+                        static_cast<unsigned long long>(roadAudit.capsuleSamples),
+                        static_cast<unsigned long long>(roadAudit.blocked),
+                        static_cast<unsigned long long>(roadAudit.supportSamples),
+                        static_cast<unsigned long long>(roadAudit.unsupported),
+                        static_cast<unsigned long long>(roadAudit.gradeFailures),widthMetres,
+                        2.0*CapsuleRadiusMetres,gradeDegrees,passed?"PASS":"FAIL");
+                }
+                if(!found&&required)
+                {
+                    std::printf("[LiminalRoadWalkAudit] status=FAIL reason=road_stamp_missing\n");
+                    return false;
+                }
+                return passed;
+            };
+            if(bAuditLiminalRoadWalk&&!bAuditResolvedLayoutPassages)
+            {
+                const bool passed=auditLiminalRoadWalk(true);
+                Streamer.Stop();
+                return passed?0:14;
+            }
             const auto qToMetres=[&](std::int64_t q)
             {return static_cast<double>(q)*World.CoreVoxelSizeMicrons
                 /(VoxelForgeCore::WorldAssemblySubvoxelsPerVoxel*1000000.0);};
@@ -4919,6 +4981,7 @@ namespace StandaloneStreamBenchmark
                         routeAudit.firstUnsupported[i][1],routeAudit.firstUnsupported[i][2],
                         routeAudit.firstUnsupported[i][3]);
             }
+            const bool liminalRoadAuditPassed=auditLiminalRoadWalk(false);
             for(std::size_t passageIndex=0;
                 passageIndex<ResolvedLayout->passages.size();++passageIndex)
             {
@@ -4984,6 +5047,7 @@ namespace StandaloneStreamBenchmark
                 &&shellAuditPassed
                 &&routePasses>0&&routePasses==routeWalkPasses&&routePasses==routeBindings
                 &&routeBindingFailures==0
+                &&liminalRoadAuditPassed
                 &&blockedCompiled&&blockedControls==passageCount;
             std::printf("[ResolvedPassageAuditSummary] interfaces=%llu passed=%llu natural=%llu/%llu strate_routes=%llu route_walkable=%llu route_points=%llu route_bindings=%llu route_binding_failures=%llu blocked_controls=%llu/%llu status=%s\n",
                 static_cast<unsigned long long>(passageCount),static_cast<unsigned long long>(passagePasses),