Verify Authorization Token

Verify an Authorization Token by its `code` value. This endpoint is used by DAFs in the **Donor-Initiated Verification** flow: when a donor presents the `code` they received from DAFpay (via email after submitting a Grant Request), the DAF calls this endpoint with the `code` to confirm the donor's identity. On success: - The Authorization Token transitions to `verified`. - The linked Donor Account is automatically transitioned to `approved` if it is currently `pending`. - The full Donor Account is returned (including the `id` you can use to call subsequent endpoints). Codes are only valid until the token's `expires_at` — **30 days** after creation by default (configurable via `expires_in` on [Create Authorization Token](/api/authorization-tokens/create), 60 seconds to 90 days). After that point, the token's status becomes `expired` and verification will fail. If the donor's code has expired, prompt them to submit a new Grant Request — DAFpay will issue and email a fresh code automatically. <Warning> Error handling: - If the `code` is unknown, expired, revoked, or already verified, the request will return status `404 Not Found` or `410 Gone` to avoid leaking information about valid codes. Expired codes are intentionally indistinguishable from other invalid codes in the response — surface a generic "code is invalid or has expired" message to the donor and ask them to request a new code. - If the linked Donor Account has already been rejected, the request will return status `409 Conflict`. - To prevent brute-force attacks, this endpoint enforces strict per-DAF rate limits. Repeated failures will return status `429 Too Many Requests`. </Warning>