Roll forward staff holiday balances with a tenure step-up, a balance cap, part-timers and a year-end carry-over limit

# Roll forward holiday balances Inputs: `employees.csv` (hire date, FTE, opening balance in hours on 2025-10-01), `leave-taken.csv` and `pto-policy.json`. Work out every employee's balance on 2026-03-31, going through the twelve semi-monthly periods from 2025-10-01 in order (1st-15th, then 16th-month end). - In each period, first subtract approved leave dated in that period (leave with status `cancelled` doesn't count), then add that period's accrual. - Accrual = the policy's base hours for the employee's tenure on the last day of the period, times FTE, rounded to 2 decimals half-up. Tenure counts whole years since `hire_date`. - Accrual stops at the cap: never add more than would take the balance above `cap_hours`. - After the period ending 2025-12-31, any balance above `carryover_max_hours` is forfeited. Write `out/balances.json`: `{"balance": {"<employee_id>": <hours on 2026-03-31>, ...}, "accrued": {"<employee_id>": <hours accrued over the 12 periods>, ...}, "forfeited": {"<employee_id>": <hours forfeited at year end>, ... only employees who forfeited}}`. Hours to 2 decimals. ## 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.