POST /api/v2/payment/off-ramp/quote

{
  "cryptoAmount": 25.0,
  "cryptoCurrency": "LISK_USDT",
  "fiatCurrency": "KES"
}

{
  "success": true,
  "data": {
    "quoteId": "quote-off-1234",
    "cryptoAmount": 25.0,
    "fiatAmount": 3250.0,
    "fiatCurrency": "KES",
    "fee": 0.5,
    "netPayout": 3185.0
  }
}

POST /api/v2/payment/off-ramp/initiate

Authorization: Bearer <jwt_access_token>

{
  "quoteId": "quote-off-1234",
  "paymentMethod": "MPESA",
  "recipientPhoneNumber": "+254712345678",
  "walletPin": "1234"
}

{
  "success": true,
  "data": {
    "orderId": "order-off-5591",
    "status": "PROCESSING",
    "estimatedCompletionMinutes": 5
  },
  "message": "Off-ramp initiated successfully"
}