Modeling Data - Add BRepProp package for modern BRep differential properties (#1116)

Add new BRepProp package to TKBRep as a thin wrapper over GeomProp:: free
functions for computing local differential properties of BRep edges and faces
without exceptions. Replaces the legacy BRepLProp macro-based (.gxx) pattern.

New package BRepProp (TKBRep) provides:
- BRepProp_Curve: Local curve property evaluator for BRep edges.
  Delegates derivative computation to BRepAdaptor_Curve and passes results
  to GeomProp::ComputeTangent, ComputeCurvature, ComputeNormal,
  ComputeCentreOfCurvature. Three Initialize overloads: from TopoDS_Edge
  (owning), from BRepAdaptor_Curve reference (non-owning), and from
  occ::handle<BRepAdaptor_Curve> (shared ownership). Includes static
  Continuity() methods for regularity analysis at curve junctions
  (replaces BRepLProp::Continuity).
- BRepProp_Surface: Local surface property evaluator for BRep faces.
  Delegates derivative computation to BRepAdaptor_Surface and passes results
  to GeomProp::ComputeSurfaceNormal, ComputeSurfaceCurvatures,
  ComputeMeanGaussian. Same three Initialize overloads as BRepProp_Curve.

Key design decisions:
- No variant dispatch needed: BRepAdaptor_Curve/Surface handle geometry-type
  dispatch internally via virtual methods, so BRepProp is a thin wrapper
  calling adaptor D1/D2/D3 then GeomProp:: free functions.
- Ownership pattern: occ::handle for owning case + raw const pointer for
  non-owning case, consistent with GeomProp_Curve/Surface.
- Returns result structs with IsDefined flags instead of throwing exceptions.

18 GTests: 11 unit tests (line, circle, box, cylinder, sphere) and
7 cross-validation tests against BRepLProp_CLProps/BRepLProp_SLProps.

src/ModelingData/TKBRep/PACKAGES.cmake

@@ -5,6 +5,7 @@ set(OCCT_TKBRep_LIST_OF_PACKAGES
   TopTools
   BRep
   BRepLProp
+  BRepProp
   BRepAdaptor
   BRepTools
   BinTools