Foundation, Modeling - NCollection modernization and BRepGraph overhaul (#1212)

- Migrate NCollection map/sequence/array size APIs from int to size_t; Size() returns size_t, Length() remains the int accessor; int overloads delegate through NbBucketsFromInt() with a negative-input guard.
- Add NCollection_LinearVector: contiguous flat-buffer dynamic array with Standard::Reallocate-based growth for trivial types and move-construction for non-trivial types.
- Rewrite NCollection_DynamicArray on top of LinearVector<T*>; switch to power-of-two block sizing with precomputed shift/mask.
- Rework NCollection_BaseMap iterator with a forward findFirst() helper (no negative-bucket arithmetic); unify ReSize/BeginResize/EndResize on size_t.
- Enable thread-safe fast path in NCollection_IncAllocator via std::shared_mutex + CAS bump allocation on atomic AvailableSize; exclusive lock is taken only for new-block allocation and list reordering.
- Remove NCollection_BasePointerVector (superseded by NCollection_LinearVector).
- Remove NCollection_BaseMap::Statistics (unused).
- Add <cstddef> include in NCollection_Primes.hxx so size_t resolves on clean builds.
- Document iterator invalidation contract on NCollection_LinearVector.
- Unify BRepGraph programmatic mutation behind EditorView: delete BuilderView (2648+552 lines); EditorView (3186+930 lines) and EditorView_Mut.cxx own both structural creation (Add*/Remove*) and field-level RAII-scoped mutation (Mut*()) with automatic OwnGen and SubtreeGen propagation.
- Add BRepGraph_MeshCache and BRepGraph_MeshView: two-tier mesh storage separating algorithm-derived caches from persistent (definition) triangulations; freshness is keyed on FaceDef.OwnGen; cache writes do not mutate the model.
- Document the MeshCache invalidation contract in BRepGraph_MeshCache.hxx (which mutations bump Face.OwnGen and how markRepModified closes the loop for Surface/Triangulation reps).
- Add BRepGraph_RefsIterator (generic flat ref scan with RefTraits dispatch) and BRepGraph_ReverseIterator (typed parent-traversal wrappers over reverse-index vectors).
- Rework RefId entity model: replace inline refs with typed RefId vectors; add OccurrenceRef and Kind::Occurrence=7; BRepGraphInc_WireExplorer now requires a VertexRefLookup.
- Rename layers for consistency: BRepGraph_ParamLayer to BRepGraph_LayerParam, BRepGraph_RegularityLayer to BRepGraph_LayerRegularity; rename BRepGraphInc_Usage to BRepGraphInc_Instance.
- Replace RootNodeIds() with RootProductIds() returning product roots only.
- Update BRepGraph and BRepGraphInc READMEs; fix stale RootNodeIds reference.
- Sweep Size() to Length() renames across ~200 callers in TKG2d, TKG3d, TKMath, TKMesh, TKBO, TKOffset, TKShHealing, TKTopAlgo, TKBRep, TKService, TKV3d, TKOpenGl, TKMeshVS, TKDE*, TKXCAF, TKXSBase, TKLCAF, TKStd, and Draw harness.
- Add GTest coverage for new containers and the BRepGraph overhaul: NCollection_DynamicArray_Test, NCollection_LinearVector_Test, BRepGraph_Fuzz_Test, BRepGraph_Iterator_Test, BRepGraph_LayerIterator_Test, BRepGraph_MeshCache_Test, BRepGraph_MutGuard_Test, BRepGraph_ReplaceVertex_Test, BRepGraph_ReverseIterator_Test, BRepGraph_ScenarioMatrix_Test, BRepGraph_TypedIdDispatch_Test, BRepGraph_WireExplorer_Test.

src/ModelingData/TKBRep/BRepGraph/BRepGraph_LayerRegistry.cxx

@@ -26,12 +26,19 @@ int BRepGraph_LayerRegistry::RegisterLayer(const occ::handle<BRepGraph_Layer>& t
   const int*           aSlot = myGuidToSlot.Seek(aGUID);
   if (aSlot != nullptr)
   {
+    const occ::handle<BRepGraph_Layer>& aPrev = myLayers.Value(*aSlot);
+    if (!aPrev.IsNull() && aPrev.get() != theLayer.get())
+    {
+      aPrev->setOwningGraph(nullptr);
+    }
+    theLayer->setOwningGraph(myOwningGraph);
     myLayers.ChangeValue(*aSlot) = theLayer;
     recomputeSubscribedKindsMask();
     return *aSlot;
   }
 
   const int aNewSlot = myLayers.Length();
+  theLayer->setOwningGraph(myOwningGraph);
   myLayers.Append(theLayer);
   myGuidToSlot.Bind(aGUID, aNewSlot);
   mySubscribedKindsMask |= theLayer->SubscribedKinds();
@@ -47,8 +54,9 @@ void BRepGraph_LayerRegistry::UnregisterLayer(const Standard_GUID& theGUID)
   if (aSlotPtr == nullptr)
     return;
 
-  const int aSlot     = *aSlotPtr;
-  const int aLastSlot = myLayers.Length() - 1;
+  const int                          aSlot     = *aSlotPtr;
+  const int                          aLastSlot = myLayers.Length() - 1;
+  const occ::handle<BRepGraph_Layer> aRemoved  = myLayers.Value(aSlot);
   if (aSlot != aLastSlot)
   {
     const occ::handle<BRepGraph_Layer>& aLastLayer = myLayers.Value(aLastSlot);
@@ -59,6 +67,22 @@ void BRepGraph_LayerRegistry::UnregisterLayer(const Standard_GUID& theGUID)
   myLayers.EraseLast();
   myGuidToSlot.UnBind(theGUID);
   recomputeSubscribedKindsMask();
+  if (!aRemoved.IsNull())
+  {
+    aRemoved->setOwningGraph(nullptr);
+  }
+}
+
+//=================================================================================================
+
+void BRepGraph_LayerRegistry::SetOwningGraph(BRepGraph* theGraph) noexcept
+{
+  myOwningGraph = theGraph;
+  for (const occ::handle<BRepGraph_Layer>& aLayer : myLayers)
+  {
+    if (!aLayer.IsNull())
+      aLayer->setOwningGraph(theGraph);
+  }
 }
 
 //=================================================================================================