- iter_claims/iter_remittances now return list[dict] (snapshot under
the lock, return outside) so slow consumers no longer hold the
write lock during iteration
- iter_claims gains payer (case-insensitive substring) and
date_from/date_to filters via the new _date_in_bounds helper
- iter_remittances wires date_from/date_to and payer
- BatchRecord split into BatchRecord837 / BatchRecord835 with
__new__ dispatch so isinstance narrows result correctly,
eliminating the four 'type: ignore[assignment]' band-aids
- BatchRecord now rejects naive parsed_at via model_validator
- to_ui_remittance's adjustmentAmount=0.0 is documented as a
TODO for sub-project 2 reconciliation
151 passed, 1 skipped (no regressions; +6 tests for new filters)
Tyler