Coding - Remove unused code and comments across various files (#968)

- Removed conditional compilation blocks (`#if 0`) that contained unused code in:
  - BRepTools_Modifier.cxx
  - AdvApp2Var_Data_f2c.hxx
  - AdvApp2Var_SysBase_baseinit.cxx
  - Extrema_FuncExtCS.cxx
  - Extrema_FuncExtSS.cxx
  - GeomProjLib.cxx
  - IntAna_IntLinTorus.cxx
  - IntAna2d_AnaIntersection_8.cxx
  - IntAna2d_Outils.cxx
  - ProjLib_CompProjectedCurve.cxx
  - ProjLib_ComputeApprox.cxx
  - ProjLib_ComputeApproxOnPolarSurface.cxx

- Cleaned up header files by ensuring proper end-of-file newlines in:
  - TKBRep_pch.hxx
  - GeomLib_Tool.hxx
  - MeshVS_SymmetricPairHasher.hxx
  - OpenGl_ShaderProgramDumpLevel.hxx
  - Graphic3d_ToneMappingMethod.hxx

src/Visualization/TKMeshVS/MeshVS/MeshVS_SymmetricPairHasher.hxx

@@ -43,4 +43,4 @@ struct MeshVS_SymmetricPairHasher
   }
 };
 
-#endif // _MeshVS_SymmetricPairHasher_HeaderFile
+#endif // _MeshVS_SymmetricPairHasher_HeaderFile

src/Visualization/TKOpenGl/OpenGl/OpenGl_ShaderProgramDumpLevel.hxx

@@ -25,4 +25,4 @@ enum OpenGl_ShaderProgramDumpLevel
   OpenGl_ShaderProgramDumpLevel_Full   //!< Shader programs source code dump in full format.
 };
 
-#endif // _OpenGl_ShaderProgramDumpLevel_H__
+#endif // _OpenGl_ShaderProgramDumpLevel_H__

src/Visualization/TKService/Graphic3d/Graphic3d_ToneMappingMethod.hxx

@@ -23,4 +23,4 @@ enum Graphic3d_ToneMappingMethod
   Graphic3d_ToneMappingMethod_Filmic    //!< Use filmic tone mapping
 };
 
-#endif // _Graphic3d_ToneMappingMethod_HeaderFile
+#endif // _Graphic3d_ToneMappingMethod_HeaderFile