New setting "Remove bookmark when saved to library" (off by default). When enabled, _maybe_unbookmark runs directly in each save callback after save_post_file succeeds -- handles DB removal, grid dot, preview state, popout sync, and bookmarks tab refresh. Wired into all 4 save paths: save_to_library, bulk_save, save_as, batch_download_to. behavior change: opt-in setting, off by default