standalone: VoxelForgeCore link-safe next to Unreal -- internals in vfcore::detail, symbol check

- The copied generator, mesher and Compat stand-ins compile inside vfcore::detail.
- CheckCoreSymbols.ps1 (run by Build.ps1) fails on any unqualified Unreal-style symbol in the
  library: 16,255 on 557f6aa, 0 now. A UE 5.7 CoreMinimal.h + VoxelForgeCore.h smoke compile passes.
- Output identical: 11 hash rows at W1/W8, routes 5642/5642, look/passage/far audits pass,
  bad-shell control fails, six captures byte-identical.
Cost, measured by me interleaved (8 workers, cold, 4 runs each, first run excluded): 0.963 s vs
0.937 s for 557f6aa, ~27 ms in shape compilation; same math, so codegen/inlining. To be found.

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

Standalone/Source/StreamingWorld.h

@@ -49,6 +49,7 @@ struct FStandaloneCpuTile
     bool bHasTopologyHash=false;
     uint64 MeshPayloadAllocatedBytes=0;
     std::array<uint64,VoxelDensityProfile::BucketCount> ProfileCycles{};
+
 };
 
 inline uint64 HashStandaloneMeshPayload(const FVoxelMeshData& Mesh)
@@ -428,6 +429,19 @@ public:
         return UpdateDesired(CameraPositionVoxels,ResidentKeys,CrossingIndex);
     }
 
+    FStandaloneStreamingUpdate StartWithDesired(const FStandaloneDesiredTileSet& InitialDesired,
+                                     const std::vector<FVoxelTileKey>& ResidentKeys={},
+                                     uint64 CrossingIndex=0)
+    {
+        Stop();
+        {
+            std::lock_guard<std::mutex> Lock(Mutex);
+            bStop=false;
+        }
+        for(int32 I=0;I<WorkerCount;++I)Workers.emplace_back([this](){WorkerLoop();});
+        return UpdateDesiredSet(InitialDesired,ResidentKeys,CrossingIndex);
+    }
+
     void SetDesiredTileFilter(const std::vector<FVoxelTileKey>& Keys)
     {
         TileFilter.clear();TileFilter.reserve(Keys.size()*2+1);
@@ -461,6 +475,33 @@ public:
             for(const auto& Key:CoreTiles)
                 NewDesired.Tiles.emplace_back(FIntVector(Key.coordinate.x,Key.coordinate.y,Key.coordinate.z),Key.lod);
         }
+        return UpdateDesiredSet(std::move(NewDesired),ResidentKeys,CrossingIndex);
+    }
+
+    std::vector<FStandaloneCpuTile> TakeReady()
+    {
+        std::vector<FStandaloneCpuTile> Out;
+        std::lock_guard<std::mutex> Lock(Mutex);
+        Out.swap(Ready);
+        for(const FStandaloneCpuTile& Tile:Out)Outstanding.erase(Tile.Key);
+        return Out;
+    }
+
+    bool IsDesired(const FVoxelTileKey& Key)const
+    {std::lock_guard<std::mutex> Lock(Mutex);return Desired.contains(Key);}
+    int32 DesiredCount()const
+    {std::lock_guard<std::mutex> Lock(Mutex);return static_cast<int32>(Desired.size());}
+    int32 FullResDesiredCount()const
+    {std::lock_guard<std::mutex> Lock(Mutex);return FullResTileCount;}
+    FIntVector CenterChunk()const
+    {std::lock_guard<std::mutex> Lock(Mutex);return CurrentDesired.CenterChunk;}
+    int32 GetWorkerCount()const{return WorkerCount;}
+    uint64 GetCacheHits()const{return CacheHitCount.load(std::memory_order_relaxed);}
+
+private:
+    FStandaloneStreamingUpdate UpdateDesiredSet(FStandaloneDesiredTileSet NewDesired,
+        const std::vector<FVoxelTileKey>& ResidentKeys,uint64 CrossingIndex)
+    {
         if(MaxLevelFilter>=0)
             NewDesired.Tiles.erase(std::remove_if(NewDesired.Tiles.begin(),NewDesired.Tiles.end(),
                 [&](const FVoxelTileKey& Key){return Key.Level>MaxLevelFilter;}),NewDesired.Tiles.end());
@@ -523,28 +564,6 @@ public:
         Wake.notify_all();
         return Stats;
     }
-
-    std::vector<FStandaloneCpuTile> TakeReady()
-    {
-        std::vector<FStandaloneCpuTile> Out;
-        std::lock_guard<std::mutex> Lock(Mutex);
-        Out.swap(Ready);
-        for(const FStandaloneCpuTile& Tile:Out)Outstanding.erase(Tile.Key);
-        return Out;
-    }
-
-    bool IsDesired(const FVoxelTileKey& Key)const
-    {std::lock_guard<std::mutex> Lock(Mutex);return Desired.contains(Key);}
-    int32 DesiredCount()const
-    {std::lock_guard<std::mutex> Lock(Mutex);return static_cast<int32>(Desired.size());}
-    int32 FullResDesiredCount()const
-    {std::lock_guard<std::mutex> Lock(Mutex);return FullResTileCount;}
-    FIntVector CenterChunk()const
-    {std::lock_guard<std::mutex> Lock(Mutex);return CurrentDesired.CenterChunk;}
-    int32 GetWorkerCount()const{return WorkerCount;}
-    uint64 GetCacheHits()const{return CacheHitCount.load(std::memory_order_relaxed);}
-
-private:
     FStandaloneCpuTile Generate(const FStandaloneTileJob& Job)
     {
         const auto StartTime=FClock::now();