Send reliable WhatsApp template messages

You are integrating the Akked WhatsApp API.

Base URL: https://akked.app
Authentication: Authorization: Bearer ak_live_YOUR_KEY
Plan requirement: an active plan with API access and a connected sender selected when the API key was created.
Rate limit: 60 authenticated send requests per API key per minute.
Credits: one account credit is reserved for each message and consumed only after the provider accepts it.
Baileys safety: unofficial senders are protected by opt-out checks, frequency caps, warm-up limits, and health pauses, but WhatsApp can still restrict unofficial automation.

Workflow:
1. GET /api/v1/senders to confirm the sender bound to the API key.
2. GET /api/v1/templates to read template contracts for that sender.
3. POST /api/v1/messages with a unique Idempotency-Key header.
4. Poll GET /api/v1/messages/{id} using the returned status_url.

POST /api/v1/messages body:
{
  "to": "+E164_PHONE",
  "template_key": "one of the contracts below",
  "language": "en or ar",
  "parameters": { "exact keys required by that template": "values" }
}

Never retry with a new Idempotency-Key when the outcome is uncertain. Reuse the same key and payload. A reused key with a different payload returns 409.

Template contracts:
- order_confirmation [en, ar]: customer_name (string, required, max 120); order_number (string, required, max 80); store_name (string, required, max 120); total (string, required, max 40); currency (string, required, max 3); items (string, required, max 2000); address (string, required, max 512); order_date (string, required, max 64)
- confirmed_reply [en, ar]: customer_name (string, required, max 120); order_number (string, required, max 80)
- cancelled_reply [en, ar]: customer_name (string, required, max 120); order_number (string, required, max 80)
- paid_order [en, ar]: customer_name (string, required, max 120); order_number (string, required, max 80); store_name (string, required, max 120); total (string, required, max 40); currency (string, required, max 3); items (string, required, max 2000); address (string, required, max 512); order_date (string, required, max 64)
- abandoned_cart [en, ar]: customer_name (string, required, max 120); store_name (string, required, max 120); total (string, required, max 40); currency (string, required, max 3); cart_step (string, required, max 120); recovery_url (string, required, max 2048)
- otp [en, ar]: code (string, required, max 10)

Important errors: 401 invalid key; 402 insufficient credits; 403 inactive Growth or sender; 404 sender/template/message not found; 409 idempotency conflict; 422 invalid payload or template parameters; 429 rate limit; 503 queue unavailable.

Generate production code that validates configuration, preserves the Idempotency-Key across retries, logs the x-request-id response header, and never logs the API secret.