fix(03-03): resolve dart analyze warnings in test files

- Remove unused drift import in daily_plan_dao_test
- Fix unused local variable in tasks_dao_test
- Switch ProviderScope to UncontrolledProviderScope in home_screen_test
  and app_shell_test to resolve riverpod_lint scoped_providers warning

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

test/features/home/data/daily_plan_dao_test.dart

@@ -1,4 +1,3 @@
-import 'package:drift/drift.dart';
 import 'package:drift/native.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:household_keeper/core/database/database.dart';