Refactor window ownership and immutable frame sampling

compositor/src/presentation.rs

@@ -36,7 +36,8 @@ pub(crate) fn take_output_feedback(
 
     for window in state.space.elements().filter(|window| {
         state
-            .window_ids
+            .windows
+            .ids()
             .get(*window)
             .is_some_and(|id| state.window_belongs_to_output(*id, output))
     }) {