fix(#530): Remove expired CGImages from cache

On long running systems, the cache would continue to grow.

On my system, after running for 15 days, the Cache 983MB, almost of the total memory usage.

Author: mrunkel

Ice/MenuBar/MenuBarItems/MenuBarItemImageCache.swift

@@ -212,7 +212,13 @@ final class MenuBarItemImageCache: ObservableObject {
             newImages.merge(sectionImages) { (_, new) in new }
         }
 
-        await MainActor.run { [newImages] in
+        // Get the set of valid item infos from all sections to clean up stale entries
+        let allValidInfos = await Set(appState.itemManager.itemCache.allItems.map(\.info))
+
+        await MainActor.run { [newImages, allValidInfos] in
+            // Remove images for items that no longer exist in the item cache
+            images = images.filter { allValidInfos.contains($0.key) }
+            // Merge in the new images
             images.merge(newImages) { (_, new) in new }
         }