Prepare a charity's quarterly tax-relief claim on donations with reach-back declarations, cancellations, company gifts and donor benefits

# Prepare a small charity's gift aid claim for the quarter Inputs: `donations.csv` (every donation received July to September 2026: donor, date, amount, donor type and the value of any benefit the donor received in return) and `declarations.csv` (gift aid declarations donors have signed, with any cancellation date). Every amount is in pounds. This is a made-up scheme for this task; follow these rules, not any real tax rules. Claim rules: - A donation is covered only if its donor has a declaration whose declaration_date is no more than 4 years after the donation date (declarations reach back up to 4 years, and cover everything after), and, if that declaration has a cancelled_date, the donation was made before the cancelled_date. - Donations from companies (donor_type 'company') are never eligible. - A donation where the donor received a benefit is eligible only if benefit_value is no more than 25% of the amount; otherwise none of it is eligible. - Gift aid = 25% of each donor's total eligible donations, rounded half-up to the cent per donor. Write `out/claim.json`: `{"covered": {"<donation_id>": true|false, ...} for every donation from an individual (whether a declaration covers it, ignoring the benefit rule), "benefit_ok": {"<donation_id>": true|false, ...} for every donation from an individual with a benefit_value, "eligible_total": {"<donor_id>": <sum of that donor's eligible donations>, ...}, "gift_aid": {"<donor_id>": <gift aid>, ...}, "claim_total": <sum of the per-donor gift aid figures>}` listing only donors with at least one eligible donation. ## 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.