refactor: add createGizmoRenderThread

thermion_dart/native/include/c_api/ThermionDartRenderThreadApi.h

@@ -55,6 +55,13 @@ namespace thermion
         EMSCRIPTEN_KEEPALIVE void load_skybox_render_thread(TViewer *viewer, const char *skyboxPath, void (*onComplete)());
         EMSCRIPTEN_KEEPALIVE void remove_skybox_render_thread(TViewer *viewer);
 
+        EMSCRIPTEN_KEEPALIVE TGizmo *SceneManager_createGizmoRenderThread(
+            TSceneManager *tSceneManager, 
+            TView *tView, 
+            TScene *tScene,
+            void (*onComplete)(TGizmo*)
+        );
+
         EMSCRIPTEN_KEEPALIVE void SceneManager_createGeometryRenderThread(
             TSceneManager *sceneManager,
             float *vertices,

thermion_dart/native/src/c_api/ThermionDartRenderThreadApi.cpp

@@ -536,6 +536,22 @@ extern "C"
     return nullptr;
   }
 
+  EMSCRIPTEN_KEEPALIVE TGizmo *SceneManager_createGizmoRenderThread(
+      TSceneManager *tSceneManager, 
+      TView *tView, 
+      TScene *tScene,
+      void (*onComplete)(TGizmo*)
+  ) {
+      std::packaged_task<void()> lambda(
+        [=]() mutable
+        {
+          auto *gizmo = SceneManager_createGizmo(tSceneManager, tView, tScene);
+          onComplete(gizmo);
+        });
+      auto fut = _rl->add_task(lambda);
+      return nullptr;
+  }
+
   EMSCRIPTEN_KEEPALIVE void *SceneManager_destroyAssetRenderThread(TSceneManager *tSceneManager, TSceneAsset *tSceneAsset, void (*callback)())
   {
     std::packaged_task<void()> lambda(