fix: adjust grid aspect ratio to prevent overflow

- Change childAspectRatio from 0.75 to 0.68 for more vertical space
- Fixes 'bottom overflowed by X pixels' error in grid cards
- Provides adequate space for square cover + title + author text
- Cards are slightly taller but layout is now correct

lib/features/library_browser/view/filtered_library_items_page.dart

@@ -77,7 +77,7 @@ class FilteredLibraryItemsPage extends HookConsumerWidget {
                 padding: const EdgeInsets.all(16),
                 gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
                   crossAxisCount: 3,
-                  childAspectRatio: 0.75,
+                  childAspectRatio: 0.68,
                   crossAxisSpacing: 12,
                   mainAxisSpacing: 16,
                 ),