feat(engine): C++ native script system (ScriptBehavior + registry)

ScriptComponent stores only a script name string (POD, serializable);
instances are reconciled by ScriptRuntime each frame (PhysicsWorld
pattern): orphan/rename cleanup with OnDestroy, per-name instantiation
from a file-level self-registering registry (ENGINE_REGISTER_SCRIPT),
OnCreate on bind, OnUpdate after physics step on scaled dt. Engine
framerate loop only sees the base interface, so future Lua/C# behaviors
plug in as foreign ScriptBehavior implementations with zero engine
changes. Ships a Spinner sample script and Inspector script picker.

App/CMakeLists.txt

@@ -1,9 +1,12 @@
-# App 层源文件：main + editor/（docking 编辑器，纯 App 代码）
+# App 层源文件：main + editor/（docking 编辑器）+ scripts/（C++ 原生脚本）
 file(GLOB EDITOR_SOURCES CONFIGURE_DEPENDS
         ${CMAKE_CURRENT_SOURCE_DIR}/editor/*.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/editor/*.h)
 
-add_executable(HelloVulkan main.cpp ${EDITOR_SOURCES})
+file(GLOB SCRIPT_SOURCES CONFIGURE_DEPENDS
+        ${CMAKE_CURRENT_SOURCE_DIR}/scripts/*.cpp)
+
+add_executable(HelloVulkan main.cpp ${EDITOR_SOURCES} ${SCRIPT_SOURCES})
 
 target_include_directories(HelloVulkan PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/editor)