v0.3.1

[0.3.1] - 2026-09-23

Fixed

• A PAC payment could not be retrieved with get_instant_payment (#15).
  Observed against the live developer-mode API in parle-cl/telemaco#377:
  GET /v3/payments/{id} for an Automatic Payments charge returned
  payment_method: "direct_debit", which Khipu's published Instant Payments
  document does not declare (it still lists only regular_transfer,
  simplified_transfer and not_available). The generated parser raised
  ValueError, so the call failed with KhipuResponseError and none of the
  verification fields could be read.

  direct_debit is now accepted for that field on that endpoint only, as a
  typed PaymentGetPaymentPaymentMethod.DIRECT_DEBIT member reachable through
  raw. InstantPaymentStatus is unchanged. Any other undeclared
  payment_method, and any undeclared status, status_detail or
  funds_source, is still reported as KhipuResponseError.

Added

• tools/spec_compat.py, a generation-time compatibility overlay.
  make generate-instant now generates from a derived copy of the Instant
  Payments spec under build/openapi/; the committed spec is still Khipu's
  document byte for byte and its sha256 lock is unchanged. The overlay's single
  entry is strict: generation fails if Khipu publishes direct_debit itself
  (the entry is then obsolete and must be deleted) or changes the enum in any
  other way. make check-spec-compat runs the same check without writing
  anything.
• CI fails when committed generated/ differs from a fresh
  make generate-all, and the spec-drift watch checks the overlay against
  the freshly published spec.

Notes

• This is a deliberate, temporary divergence from Khipu's published schema,
  kept only until Khipu documents direct_debit. No retry behaviour changed and
  nothing new is logged.