Sets the underwriting result for the tenant with the given external ID.

By default, all tenants pass underwriting in sandbox — so this endpoint is only needed when testing the declined flow or explicitly overriding the default behavior.

ℹ️ This pre-configures the outcome of the underwriting flow — the result only takes effect once the tenant completes the underwriting flow in the Livble widget.

WILL_BE_APPROVED — the tenant will pass underwriting. WILL_BE_DECLINED — the tenant will fail underwriting.

⚠️ This mock persists until explicitly changed by calling this endpoint again.