Full transaction history for a PIID — every modification row, oldest to newest

Returns every transaction row for the given PIID, oldest action first.

Modification trail use case: amendments, options exercised, partial terminations. Each row is a single FPDS action; mods stack on the original award. Not date-windowed by request (no date_from/to params — a caller asking for one PIID's history gets everything WE HOLD for it), but prime_awards itself only carries FY2025 onward (CONTRACTS_DATA_FLOOR), so an order whose PoP predates that floor silently starts mid-sequence (e.g. first modification_number P00026, not P00001). Disclosed via the same window block search_contracts/search_vehicles/search_subawards use.