CAM: Add open-route optimizations to point-based TSP solver

Improves the point-based TSP solver to match tunnel solver behavior
for open routes (no endpoint constraint). Now applies 2-opt and
relocation optimizations that allow reversing or relocating segments
to the end of the route, resulting in better path optimization when
the ending point is flexible. Now links tsp_solver with
Python3::Python and uses add_library for compatibility with FreeCAD
and Fedora packaging.

src/Mod/CAM/App/tsp_solver.cpp:
- Add optimization limit variables for controlled iteration
- Add 2-opt and relocation optimizations for open routes
- Use Base::Precision::Confusion() for epsilon values
- Track last improvement step for efficient loop control

src/Mod/CAM/App/CMakeLists.txt:
- Switch tsp_solver from pybind11_add_module to add_library
- Link tsp_solver with pybind11::module and Python3::Python
- Update include directories for consistency

package/fedora/freecad.spec

@@ -29,7 +29,7 @@ Source0:        freecad-sources.tar.gz
 
 # Maintainers:  keep this list of plugins up to date
 # List plugins in %%{_libdir}/%%{name}/lib, less '.so' and 'Gui.so', here
-%global plugins AssemblyApp AssemblyGui CAMSimulator DraftUtils Fem FreeCAD Import Inspection MatGui Materials Measure Mesh MeshPart Part PartDesignGui Path PathApp PathSimulator Points QtUnitGui ReverseEngineering Robot Sketcher Spreadsheet Start Surface TechDraw Web _PartDesign area flatmesh libDriver libDriverDAT libDriverSTL libDriverUNV libE57Format libMEFISTO2 libSMDS libSMESH libSMESHDS libStdMeshers libarea-native
+%global plugins AssemblyApp AssemblyGui CAMSimulator DraftUtils Fem FreeCAD Import Inspection MatGui Materials Measure Mesh MeshPart Part PartDesignGui Path PathApp PathSimulator Points QtUnitGui ReverseEngineering Robot Sketcher Spreadsheet Start Surface TechDraw Web _PartDesign area flatmesh libDriver libDriverDAT libDriverSTL libDriverUNV libE57Format libMEFISTO2 libSMDS libSMESH libSMESHDS libStdMeshers libarea-native tsp_solver
 
 %global exported_libs libOndselSolver