test: Java-Konvergenz- + Homologie-Tests portiert — 173 CGAL-Tests

Mesh-Dateien aus Java-Referenzimplementierung übernommen:
  code/data/obj/cathead.obj    — offenes Mesh (Java: cathead.obj)
  code/data/obj/tetraflat.obj  — flaches Tetraeder (Java: tetraflat.obj)
  code/data/obj/brezel.obj     — Genus-1-Brezel (Java: brezel.obj)
  code/data/obj/brezel2.obj    — Genus-2-Brezel, V=2622 F=5248 χ=−2 (Java: brezel2.obj)
code/.gitignore: !data/**/*.obj — Mesh-Daten von *.obj-Regel ausgenommen.

Neue Tests in test_geometry_utils.cpp:

  HomologyGenerators.Genus2_FourCutEdges                    [vorher: GTEST_SKIP]
    Java: HomologyTest.testHomology — brezel2.obj, expects paths.size()==4
    C++:  compute_cut_graph(brezel2) → cut_edge_indices.size()==4, genus==2

  EuclideanLayout.DoLayout_TetraFlat_EdgeLengthsPreserved   [neu]
    Java: EuclideanLayoutTest.testDoLayout — tetraflat.obj, u=0, l3D==lUV (1e-11)
    C++:  euclidean_layout(tetraflat, x=0) → alle UV-Kantenlängen == 3D (1e-10)

  EuclideanLayout.CatHead_NewtonConverges_AngleSumsTwoPi    [neu]
    Java: EuclideanLayoutTest.testLayout02 + EuclideanCyclicConvergenceTest
    C++:  newton_euclidean(cathead) konvergiert, Gradientenreste < 1e-6

  SphericalLayout.SphericalTetrahedron_NewtonConverges_AngleSumsTwoPi [neu]
    Java: SphericalConvergenceTest.testSphericalConvergence
    C++:  newton_spherical(sph_tetrahedron) konvergiert, Winkeldefekte < 1e-6

CMakeLists.txt: CONFORMALLAB_DATA_DIR=${CMAKE_SOURCE_DIR}/data als Compile-Def.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

code/.gitignore

@@ -40,6 +40,8 @@ Thumbs.db
 *.lo
 *.o
 *.obj
+# Exception: mesh data files in code/data/ are not compiled objects
+!data/**/*.obj
 
 # Precompiled Headers
 *.gch