docs: elaborate on what can be included in the createApp root props (#1123)

Author: skirtles-code

src/api/global-api.md

@@ -63,6 +63,8 @@ const app = createApp(
 </div>
 ```
 
+The root props are raw props, much like those passed to [`h`](#h) to create a VNode. In addition to component props, they can also include attributes and event listeners to be applied to the root component.
+
 ### Typing
 
 ```ts