fix: compilation + test fixes — 26/42 failures resolved

- CAM offset: fix knot collision in fit_clamped/make_circle → NaN
- Face split: fix add_face returning global ID instead of index → SEGFAULT
- Volume: fix formula to use abs-per-face for orientation robustness
- Build: fix vde_mesh linking, add vde_collision to vde_brep deps
- Tests: fix surface_intersection test, fuzz CMake, face split expectations
- Rename test_constraint_solver → test_constraint_solver_3d (naming conflict)
- Various include/namespace fixes across test files

tests/brep/test_brep_face_split.cpp

@@ -2,10 +2,12 @@
 #include "vde/brep/brep.h"
 #include "vde/brep/modeling.h"
 #include "vde/brep/brep_face_split.h"
+#include "vde/curves/nurbs_surface.h"
 #include <cmath>
 
 using namespace vde::brep;
 using namespace vde::core;
+using namespace vde::curves;
 
 // ═══════════════════════════════════════════════════════════
 //  Face Splitting by Plane
@@ -32,17 +34,11 @@ static int total_verts(const std::vector<BrepModel>& frags) {
 TEST(BrepFaceSplitTest, SplitBoxFace_ByYZPlane_YieldsTwoFragments) {
     auto box = make_box(2, 2, 2);  // centered at origin, spans [-1,1]³
 
-    // Face 0 is the front face (-X side), a quad covering x=-1
-    // Cutting with YZ plane (x=0) should split this face
-    // All vertices of face 0 are at x=-1, all on negative side → single fragment
-    // Let's use face 0's vertices: they're all at x=-1
-
-    // Instead, split face 0 with a plane that actually cuts it.
-    // Face vertices are at x=-1, so use plane x = -0.5
-    auto frags = split_face_by_plane(box, 0,
+    // Face 5 is the x=-1 face (left side). All its vertices have x=-1.
+    // Plane x=-0.5 has all face vertices on negative side → no split.
+    auto frags = split_face_by_plane(box, 5,
         Point3D(-0.5, 0, 0), Vector3D(1, 0, 0));
 
-    // All vertices are at x=-1 (negative side of x=-0.5) → single fragment
     EXPECT_EQ(frags.size(), 1u);
     EXPECT_TRUE(frags[0].is_valid());
     EXPECT_EQ(frags[0].num_faces(), 1u);
@@ -56,18 +52,10 @@ TEST(BrepFaceSplitTest, SplitBoxFace_ByYZPlane_YieldsTwoFragments) {
 TEST(BrepFaceSplitTest, SplitBoxFace_PlaneThroughCenter_YieldsTwoFragments) {
     auto box = make_box(2, 2, 2);  // centered at origin
 
-    // Build a face that straddles a plane by defining the plane
-    // in the middle of the box.
-    // We'll verify that splitting a face where the plane
-    // goes through its interior produces 2 fragments.
-
-    // Use x=0 plane. Some box faces are at x=±1, those won't split.
-    // But we can also test with a different plane.
-
-    // Face 0 is at x=-1. Let's check face 0:
-    auto frags0 = split_face_by_plane(box, 0,
+    // Face 5 is at x=-1 (all vertices have x = -1).
+    // Plane x=0 leaves it entirely negative → no split.
+    auto frags0 = split_face_by_plane(box, 5,
         Point3D(0, 0, 0), Vector3D(1, 0, 0));
-    // All vertices are at x=-1 → no split
     EXPECT_EQ(frags0.size(), 1u);
 
     // Actually, let's create a face that crosses the plane by
@@ -100,8 +88,9 @@ TEST(BrepFaceSplitTest, FaceOnOneSide_ReturnsSingleFragment) {
     // All box faces are axis-aligned planes. A cutting plane far
     // outside the face will leave it entirely on one side.
 
-    // Face 0 is at x=-1, use cutting plane at x=10
-    auto frags = split_face_by_plane(box, 0,
+    // Face 5 is at x=-1 (all x coordinates are -1)
+    // Cutting plane at x=10 is far away → face entirely on negative side.
+    auto frags = split_face_by_plane(box, 5,
         Point3D(10, 0, 0), Vector3D(1, 0, 0));
 
     EXPECT_EQ(frags.size(), 1u);
@@ -109,7 +98,7 @@ TEST(BrepFaceSplitTest, FaceOnOneSide_ReturnsSingleFragment) {
     EXPECT_EQ(frags[0].num_faces(), 1u);
 
     // Fragment should have the same number of vertices as original face
-    auto orig_edges = box.face_edges(0);
+    auto orig_edges = box.face_edges(5);
     EXPECT_EQ(frags[0].num_vertices(), orig_edges.size());
 }
 
@@ -153,7 +142,7 @@ TEST(BrepFaceSplitTest, PlaneThroughEdge_YieldsTwoFragments) {
         {Point3D(0, 2, 0), Point3D(0, 0, 0)},
         {Point3D(2, 2, 0), Point3D(2, 0, 0)}
     };
-    curves::NurbsSurface surf(grid, {0,0,1,1}, {0,0,1,1}, {}, 1, 1);
+    NurbsSurface surf(grid, {0,0,1,1}, {0,0,1,1}, std::vector<std::vector<double>>{}, 1, 1);
     int sid = tri.add_surface(surf);
 
     int face_id = tri.add_face(sid, {loop});
@@ -209,7 +198,7 @@ TEST(BrepFaceSplitTest, PlaneThroughVertex_YieldsTwoFragments) {
         {Point3D(0, 2, 0), Point3D(0, 0, 0)},
         {Point3D(2, 2, 0), Point3D(2, 0, 0)}
     };
-    curves::NurbsSurface surf(grid, {0,0,1,1}, {0,0,1,1}, {}, 1, 1);
+    NurbsSurface surf(grid, {0,0,1,1}, {0,0,1,1}, std::vector<std::vector<double>>{}, 1, 1);
     int sid = tri.add_surface(surf);
 
     int face_id = tri.add_face(sid, {loop});
@@ -249,7 +238,7 @@ TEST(BrepFaceSplitTest, BoxFaceStraddlingPlane) {
         {Point3D(-1, 0,  1), Point3D(-1, 0, -1)},
         {Point3D( 1, 0,  1), Point3D( 1, 0, -1)}
     };
-    curves::NurbsSurface surf(grid, {0,0,1,1}, {0,0,1,1}, {}, 1, 1);
+    NurbsSurface surf(grid, {0,0,1,1}, {0,0,1,1}, std::vector<std::vector<double>>{}, 1, 1);
     int sid = quad.add_surface(surf);
 
     int loop_id = quad.add_loop({e0, e1, e2, e3}, true);
@@ -329,7 +318,7 @@ TEST(BrepFaceSplitTest, DiagonalPlane_SplitsQuadFace) {
         {Point3D(-1,  1, 0), Point3D(-1, -1, 0)},
         {Point3D( 1,  1, 0), Point3D( 1, -1, 0)}
     };
-    curves::NurbsSurface surf(grid, {0,0,1,1}, {0,0,1,1}, {}, 1, 1);
+    NurbsSurface surf(grid, {0,0,1,1}, {0,0,1,1}, std::vector<std::vector<double>>{}, 1, 1);
     int sid = quad.add_surface(surf);
 
     int loop_id = quad.add_loop({e0, e1, e2, e3}, true);