Raise self-storage invoices with a notice-dependent rent rise, pro-rata move-ins and move-outs, contents insurance and late fees

# Raise a self-storage site's November invoices Inputs: `units.csv` (each storage unit and its current monthly rent), `tenancies.csv` (who rents which unit, move-in and move-out dates, declared contents value, and when they were sent the rent-rise notice), `balances.csv` (unpaid balance carried from October) and `terms.json`. Every amount is in pounds. Invoice every tenancy that occupies its unit on at least one day of November 2026. Invoice rules, per tenancy: - The 6% rent rise applies from 1 November only if the tenant's rent_notice_date is at least 30 days before 1 November; otherwise the old rent applies all month. - A tenancy that starts or ends during November pays rent pro rata: monthly rent x days occupied / 30, counting both the move-in day and the move-out day. - Round the November rent to the cent half-up after the rise and any pro rata. - Insurance is 1.95 per started 1,000 of declared_value, charged for the whole month whatever the days occupied. - A late fee of 10% of the unpaid October balance is added when that balance is more than 0, rounded to the cent half-up. Write `out/invoices.json`: `{"rent": {"<tenancy_id>": <rent>, ...}, "insurance": {...}, "late_fee": {...}, "total": {"<tenancy_id>": <rent + insurance + late fee + unpaid balance>, ...}, "grand_total": <sum of totals>}` with every invoiced tenancy and no others. ## 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.