* Refactor code for lifespan, template usage, and improved tests
- Move background tasks and rate-limit handler into utils.py
- Reference TEMPLATES from config instead of inline Jinja2Templates
- Adopt Given/When/Then docstrings for test clarity
- Parametrize some tests and consolidate code across query_parser tests
- Add pytest.warns context handler to test_parse_repo_source_with_failed_git_command
- Introduce ParsedQuery dataclass to store query parameters and metadata
- Update ingestion and parser modules to use ParsedQuery instead of dict[str, Any]
- Convert ignore_patterns and include_patterns to sets
- Clean references to max size and pattern handling
- Update tests to reflect new dataclass usage
