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/foundation/serializer.h

@@ -23,16 +23,16 @@ struct SerializedMesh {
 class BinarySerializer {
 public:
     /// Serialize mesh to binary buffer
-    static std::vector<uint8_t> serialize(const HalfedgeMesh& mesh);
+    static std::vector<uint8_t> serialize(const mesh::HalfedgeMesh& mesh);
 
     /// Deserialize mesh from binary buffer
-    static HalfedgeMesh deserialize(const std::vector<uint8_t>& data);
+    static mesh::HalfedgeMesh deserialize(const std::vector<uint8_t>& data);
 
     /// Write to file
-    static bool write_file(const std::string& path, const HalfedgeMesh& mesh);
+    static bool write_file(const std::string& path, const mesh::HalfedgeMesh& mesh);
 
     /// Read from file
-    static HalfedgeMesh read_file(const std::string& path);
+    static mesh::HalfedgeMesh read_file(const std::string& path);
 };
 
 }  // namespace vde::foundation