Bill an upholstery workshop's finished jobs from its job cards, fabric rounding and customer deposits

# Bill an upholstery workshop's finished jobs from its job cards, fabric rounding and customer deposits Inputs: `upholsterers.csv` (upholsterer_id, name, rate_per_hour), `customers.csv` (customer_id, name), `fabrics.csv` (fabric_code, price_per_metre), `jobs.csv` (job_id, customer_id, upholsterer_id, fabric_code, fabric_m, labour_hours, status) and `deposits.csv` (customer_id, amount). All upholsterers, customers, fabrics and jobs are synthetic; prices are in dollars. These rules are the workshop's; where `workshop-notes.txt` disagrees, the rules win. Rules: - Statuses: `done` jobs are billed. `rework` jobs redo the workshop's own faulty work: they are free, but their labour_hours still count as hours worked. `cancelled` jobs count nowhere. - Fabric: a billed job's fabric is charged by the half metre. Its billed metres are fabric_m rounded up to the next multiple of 0.5 (a fabric_m that is already a multiple of 0.5 stays as it is), times its fabric's price_per_metre. - Labour: a billed job's labour is labour_hours × its upholsterer's rate_per_hour. - Discount: a billed job's charge is its fabric plus its labour, less 10% when that sum is 600.00 or more. Don't round until the output. - Hours: an upholsterer's hours are the labour_hours of their `done` and `rework` jobs. - Balances: a customer's balance is the total charge of their billed jobs minus the total of their rows in deposits.csv. - Write `out/workshop.json`: `{"billed_jobs": [<sorted job_ids>], "fabric_metres_billed": <total billed metres>, "discounted_jobs": [<sorted job_ids>], "billed_total": <dollars>, "takings_by_upholsterer": {"<upholsterer_id>": <dollars>, ...}, "hours_by_upholsterer": {"<upholsterer_id>": <hours>, ...}, "balance_by_customer": {"<customer_id>": <dollars>, ...}}`. - Roll-ups: In takings_by_upholsterer, upholsterers in upholsterers.csv with no billed jobs are included at 0. In hours_by_upholsterer, upholsterers in upholsterers.csv with no done or rework jobs are included at 0. In balance_by_customer, customers in customers.csv with no billed jobs and no deposits are included at 0. ## 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.