This commit resolves an `ImportError` by centralizing all lead parsing logic into `ingest.py`.
- **Move `parse_tradingtwins_html`:** The function for parsing TradingTwins HTML emails has been moved from `trading_twins_ingest.py` to `ingest.py`.
- **Move `is_free_mail`:** The utility function `is_free_mail` was also moved from `trading_twins_ingest.py` to `ingest.py` to be shared by all parsers.
- **Update Imports:** The import statement in `trading_twins_ingest.py` is now corrected to import all necessary functions from the central `ingest.py` module.
This refactoring improves code structure, removes redundancy, and fixes the critical bug that prevented the ingest process from running.
