Instagram Webhook Receive

Receive real-time webhook events from Meta (comments, DMs, story replies).

Meta requires HTTP 200 within 5 seconds, so the engine cannot run inline here — but it must not run after the response either. On Vercel the process is frozen the instant the response is written (same reason main.py flushes Sentry per-request), so a FastAPI BackgroundTask can be killed mid-flight; because we already returned 200, Meta never redelivers and the event is gone for good.

So: verify the signature, put the event on a durable queue before ACKing, and let the automation-worker Lambda drive it back through /webhook/process. If the enqueue fails we 5xx, which is what makes Meta retry.