docs: Add Component, GameObject, TransformComponent and Scene API documentation

- Add Component class documentation with lifecycle methods
- Add GameObject class documentation with component system
- Add TransformComponent documentation with transform methods
- Add Scene class documentation with GameObject management
- Add SceneManager singleton documentation with scene loading
- Update components.md overview with all component classes
- Update main.md navigation with Scene module

docs/api/scene/scene/get-root-game-objects.md

@@ -0,0 +1,27 @@
+# GetRootGameObjects
+
+Get all root-level GameObjects in this scene.
+
+## Syntax
+
+```cpp
+std::vector<GameObject*> GetRootGameObjects() const;
+```
+
+## Returns
+
+Returns a `std::vector` containing pointers to all root-level GameObjects.
+
+## Remarks
+
+Root-level GameObjects are those without a parent within the scene hierarchy.
+
+## Examples
+
+```cpp
+void Example(Scene* scene) {
+    for (GameObject* go : scene->GetRootGameObjects()) {
+        XC_LOG_INFO("Root object: {}", go->GetName());
+    }
+}
+```