- Added the ability to archive and unarchive chat threads, enhancing user interaction with chat items.
- Introduced a new `handleChatArchive` function to manage the archiving state and provide user feedback via toast notifications.
- Updated the `ChatItem` type to include an `archived` property for tracking the archive status.
- Modified relevant components to support the new archiving feature, including `ChatListItem`, `Sidebar`, and `MobileSidebar`.