Foundation Classes - Optimize and fix Bnd package (#839)

Foundation Classes - Optimize and fix Bnd package (#839)

- Fixed multiple bugs including uninitialized variables (zmin/zmax in IsOut(gp_Lin)), incorrect type usage (Standard_Integer → Standard_Boolean), and improper gap handling
- Optimized performance-critical methods through branchless operations, early exits, and cached computations
- Modernized codebase with C++17 features including constexpr constructors, noexcept specifications, and [[nodiscard]] attributes
- Refactor Bnd_Box and Bnd_Box2d classes to introduce GetXMin, GetXMax, GetYMin, GetYMax, and GetZMin,
  GetZMax methods for improved clarity and encapsulation.
- Add Limits struct to represent box limits in both classes.