domain/log_level library

1. log_er package
2. documentation
3. domain/log_level.dart

log_er package

1. Libraries
2. application/log_service
3. core/ansi_colors
4. core/log_formatter
5. core/log_wrapper
6. domain/log_level
7. domain/log_repository
8. infrastructure/api_logger
9. infrastructure/console_logger
10. infrastructure/file_logger
11. log_er