Audit a taxi firm's fares for night and holiday rates, mixed distance units and started waiting minutes

# Audit a taxi firm's December fares against the tariff Inputs: `trips.csv` (trip_id, date, start_time, distance, unit, waiting_seconds, claimed_fare), `tariff.json` and `office-summary.txt`. Every amount is in pounds. The tariff file is the record; where the summary disagrees with it, the tariff wins. Rules: - The night per-mile rate applies to a trip that starts at or after night_from or before night_to, or whose date is listed in holidays; otherwise the day rate applies. The rate for the whole trip follows its start. - Distances with unit km are converted to miles by dividing by km_per_mile. - Waiting is charged per started minute (61 seconds is 2 minutes). - Fare = flag_fall + miles x per-mile rate + waiting minutes x waiting_per_minute, rounded half-up to the nearest 0.10. - A trip is overcharged if claimed_fare is more than 0.05 above the correct fare, and undercharged if it is more than 0.05 below it. Write `out/fare-audit.json`: `{"fares": {"<trip_id>": <correct fare>, ...}, "overcharged": [<sorted trip_ids>], "undercharged": [<sorted trip_ids>], "total": <sum of correct fares>}` with every trip in `fares`. ## How this run works - Work on your own: nobody will answer questions in this task, and writing to `ask/` counts against the run. - Write only under `out/`. Create `out/` if it is missing. Inputs are synthetic; don't fetch anything from the network. - Scoring is partial credit: each listed check is pass/fail, and the score is the share passed. Numbers are compared to within 0.005 unless the task says otherwise.