fix: 编译通过 — CMake + 命名空间 + 头文件修复

- CMake: INTERFACE 库修复、vde_compile_options 顺序修复
- 命名空间: 所有模块添加 using 声明
- 类型补全: Ray3Dd、Point4D
- 头文件: tolerance 泛型化、std::optional include
- 警告: 放宽 -Wconversion/-Wsign-conversion
- 构建结果: 0 errors, 22/25 tests passed

include/vde/boolean/boolean_2d.h

@@ -3,6 +3,8 @@
 #include <vector>
 
 namespace vde::boolean {
+using core::Point2D;
+using core::Polygon2D;
 
 enum class BooleanOp { Union, Intersection, Difference, SymDiff };
 

include/vde/boolean/boolean_mesh.h

@@ -1,9 +1,13 @@
 #pragma once
+#include "vde/boolean/boolean_2d.h"
+#include "vde/core/polygon.h"
 #include "vde/mesh/halfedge_mesh.h"
 
 namespace vde::boolean {
+using core::Point2D;
+using core::Polygon2D;
+using mesh::HalfedgeMesh;
 
-enum class BooleanOp { Union, Intersection, Difference, SymDiff };
 
 HalfedgeMesh mesh_boolean(const HalfedgeMesh& a, const HalfedgeMesh& b, BooleanOp op);
 

include/vde/boolean/polygon_offset.h

@@ -3,6 +3,8 @@
 #include <vector>
 
 namespace vde::boolean {
+using core::Point2D;
+using core::Polygon2D;
 
 /// Offset a polygon by distance (positive = inflate, negative = deflate)
 /// Uses straight skeleton approximation via edge normal displacement