Check sandbox bank eligibility

Returns deterministic sandbox eligibility-summary metadata when the authenticated automation client has banks.eligibility.read. External URL: /v1/banks/current/eligibility. Current Next.js implementation path: /api/platform/v1/banks/current/eligibility. This deterministic sandbox check does not require Idempotency-Key because it performs no writes, provider calls, live quote generation, application creation, callback delivery, or document handoff. It returns eligibility summary, consent metadata, redaction boundaries, and blocked side effects only and never exposes bank secrets, raw MyInfo, credit bureau data, bank statements, raw document contents, NRIC/FIN, income-proof contents, full financial profile data, borrower-specific pricing, signed storage URLs, callback signing secrets, provider calls, or enterprise ingress claims. Live bank eligibility remains unavailable until promotion gates have REST, consent, audit, sandbox, callback, and operations evidence. Bank pilot posture remains information/referral and pre-approval only, recommendation and live bank-decision claims remain deferred, and partner-status publication remains private-first.