US-4.3implemented Generate hledger rules files for a bank
As a user setting up a new bank account I want run `hledger_preprocessor --generate-rules` to create `.rules` files that tell hledger-flow how to convert my bank's CSV format into journal entries so that `hledger-flow import` can process my CSVs without manual rules authoring.
Acceptance Criteria
- A `.rules` file is generated per account configuration.
- The rules file maps CSV columns to hledger fields (date, amount, description).
- The rules file includes categorisation logic (if rule-based classification is enabled).
No DAG diagram: Setup utility — generates .rules files from config; produces a side-artifact, not data that flows through the main DAG layers.
Demo video coming soon