fix: remove duplicate separator in the shelves dropdown

frontend/src/lib/components/layout/library-switcher.svelte

@@ -35,6 +35,9 @@
 							<span class="ml-1 truncate font-semibold">
 								{libraryState.activeLibrary!.name}
 							</span>
+							<span class="ml-1 truncate font-mono text-xs tabular-nums text-muted-foreground">
+								{libraryState.activeLibrary!.total ?? 0} books
+							</span>
 						</div>
 						<ChevronsUpDownIcon class="mr-2 ml-auto" />
 					</Sidebar.MenuButton>

frontend/src/lib/components/view/batch-operations-toolbar.svelte

@@ -59,8 +59,7 @@
 					<DropdownMenu.Content>
 						<DropdownMenu.Group>
 							<DropdownMenu.GroupHeading>Shelves</DropdownMenu.GroupHeading>
-							<DropdownMenu.Separator />
-							{#each bookshelfState.getBookshelves(libraryState.activeLibrary!.id) as shelf}
+							{#each bookshelfState.getBookshelves(libraryState.activeLibrary!.id) ?? [] as shelf (shelf.id)}
 								<DropdownMenu.CheckboxItem
 									checked={selectedBooks.every(
 										(book) => book.lists.findIndex((sh) => sh.id === shelf.id) !== -1