Create and authorize a TrueLayer VRP sweeping mandate and initiate individual sweep payments

Verified steps

1. Authenticate with the recurring-payments:sweeping scope in addition to the payments scope; POST /v3/mandates with type: sweeping and constraints including maximum_individual_amount, periodic_limits (max_amount and period_type), valid_from, and valid_to
2. Receive the mandate id and resource_token; render TrueLayer's Mandate Authorization SDK or hosted page using the resource_token so the PSU can authorize with their bank — SCA happens here and only here for sweeping
3. After authorization, poll GET /v3/mandates/{mandateId} until status is authorized; store the mandateId permanently for subsequent payment initiation
4. Initiate each sweep by POST /v3/mandates/{mandateId}/payments with amount_in_minor, currency, and a unique payment_idempotency_key; no further PSU interaction is required if the amount and frequency are within the mandate constraints
5. Monitor mandate status via GET /v3/mandates/{mandateId}; check consumed_periodic_amounts against the periodic limit to predict when the limit will be reached and proactively renew or notify the user
6. To revoke a mandate, call DELETE /v3/mandates/{mandateId}; also handle inbound revocation notifications via webhook (mandate_revoked event) for PSU-initiated revocations at their bank