Sync SDL3 wiki -> header

docs/README-main-functions.md

@@ -175,10 +175,10 @@ int SDL_AppEvent(const SDL_Event *event);
 ```
 
 This will be called whenever an SDL event arrives, on the thread that runs
-SDL_AppIterate. You don't need to call SDL_CleanupEvent(), and your app
-should not call SDL_PollEvent, SDL_PumpEvent, etc, as SDL will manage this
-for you. Return values are the same as from SDL_AppIterate(), so you can
-terminate in response to SDL_EVENT_QUIT, etc.
+SDL_AppIterate. You should not call SDL_CleanupEvent() on the provided
+event, and your app should also not call SDL_PollEvent, SDL_PumpEvent, etc,
+as  SDL will manage all this for you. Return values are the same as from
+SDL_AppIterate(), so you can terminate in response to SDL_EVENT_QUIT, etc.
 
 
 Finally: