fix: S9 测试 namespace 修复 (core→vde) + unused variable 消除

tests/boolean/test_boolean_mesh.cpp

@@ -5,7 +5,7 @@
 
 using namespace vde::boolean;
 using namespace vde::mesh;
-using core::Point3D;
+using vde::Point3D;
 
 // ── Helper: build a box mesh (12 triangles, 8 vertices) ──
 // Face normals point outward (CCW winding from outside)

tests/brep/test_brep.cpp

@@ -4,8 +4,8 @@
 #include <cmath>
 
 using namespace vde::brep;
-using core::Point3D;
-using core::Vector3D;
+using vde::Point3D;
+using vde::Vector3D;
 
 // ═══════════════════════════════════════════════════════════
 //  Basic entity creation (box, sphere, cylinder)

tests/mesh/test_delaunay_3d.cpp

@@ -3,7 +3,7 @@
 #include <cmath>
 
 using namespace vde::mesh;
-using core::Point3D;
+using vde::Point3D;
 
 // ── Helper: compute circumsphere center and radius of 4 points ──
 // Returns (center, radius_squared). If points are coplanar, radius_sq < 0.
@@ -53,6 +53,7 @@ static bool verify_empty_circumsphere(
         if (r2 < 0.0) continue; // degenerate
 
         double r = std::sqrt(r2);
+        (void)r;  // explicitly unused, computed for potential debugging
         for (const auto& pt : input_points) {
             // Skip vertices of this tetrahedron
             double d2 = (pt - center).squaredNorm();