feat: Editor Gizmo——ImGuizmo 平移/旋转/缩放操纵杆

- ImGuizmo 接入：Lib/ImGuizmo（src/ 布局）静态库，IMGUI_DEFINE_MATH_OPERATORS
- ViewportPanel：Vulkan→GL 投影转换（Y 翻回 + 深度 [-1,1]）、
  SetDrawlist/SetRect 叠加绘制、decompose 写回 TransformComponent
- W/E/R 切换（UE 语义）；拖拽中 BlockingMouse 门控（输入归 Gizmo）
- Dynamic 刚体选中提示：物理每帧写回，编辑被覆盖
- 修复：GizmoState.op 初值 0 无轴位（ImGuizmo::TRANSLATE=7）导致杆不绘制
- 点击拾取门控：抓杆时（IsOver/IsUsing）不发 pick 请求

Engine/CMakeLists.txt

@@ -17,6 +17,16 @@ target_include_directories(imgui PUBLIC
 # 两个 backend 头文件分别依赖 GLFW / Vulkan 头
 target_link_libraries(imgui PUBLIC glfw Vulkan::Vulkan)
 
+# ImGuizmo（视口操纵杆，vendored submodule；新版仓库源码在 src/，
+# 只编译 ImGuizmo.cpp，GraphEditor/ImCurveEdit 等示例模块不用）
+# IMGUI_DEFINE_MATH_OPERATORS 必须 PUBLIC：ImGuizmo.cpp 与任何
+# include 其头文件的 TU 都要在 imgui.h 之前看到该宏（ImVec2 运算符）
+set(IMGUIZMO_DIR ${CMAKE_SOURCE_DIR}/Lib/ImGuizmo/src)
+add_library(ImGuizmo STATIC ${IMGUIZMO_DIR}/ImGuizmo.cpp)
+target_include_directories(ImGuizmo PUBLIC ${IMGUIZMO_DIR})
+target_compile_definitions(ImGuizmo PUBLIC IMGUI_DEFINE_MATH_OPERATORS)
+target_link_libraries(ImGuizmo PUBLIC imgui)
+
 # Tracy（CPU/GPU 帧分析）
 add_library(tracy STATIC ${CMAKE_SOURCE_DIR}/Lib/tracy/public/TracyClient.cpp)
 target_include_directories(tracy PUBLIC ${CMAKE_SOURCE_DIR}/Lib/tracy/public)
@@ -64,6 +74,7 @@ target_link_libraries(Engine PUBLIC
         meshoptimizer
         Jolt::Jolt
         imgui
+        ImGuizmo
         tracy)
 
 target_compile_definitions(Engine PRIVATE VULKAN_HPP_DISPATCH_LOADER_DYNAMIC=1)