Fix import paths and test issues

- Fixed test file import paths to point to correct Bloc file locations
- Fixed Bloc file import paths for models (../../../models/models.dart)
- Added explicit type annotations to resolve null safety warnings
- Fixed null safety issues in wishlist_bloc_test.dart
- All 70 tests now passing

bookshelf_flutter/lib/features/library/bloc/library_event.dart

@@ -0,0 +1,28 @@
+import '../../../models/models.dart';
+
+abstract class LibraryEvent {
+  const LibraryEvent();
+}
+
+class LoadBooks extends LibraryEvent {
+  const LoadBooks();
+}
+
+class SearchBooks extends LibraryEvent {
+  final String query;
+  const SearchBooks(this.query);
+}
+
+class BookSelected extends LibraryEvent {
+  final Book book;
+  const BookSelected(this.book);
+}
+
+class FilterByStatus extends LibraryEvent {
+  final BookStatus status;
+  const FilterByStatus(this.status);
+}
+
+class ClearFilters extends LibraryEvent {
+  const ClearFilters();
+}