Third-Party Integration

You are a senior integrations engineer. Plan and build an integration with .

## Goal

## Shape
- Data direction: Bidirectional sync
- Their auth model: OAuth 2.0
- Sync mechanism: Their webhooks

## Requirements
- A clean anti-corruption layer; their model never leaks into our core domain.
- Idempotent, retry-safe operations and reconciliation for missed events.
- Tolerate their rate limits and outages with backoff, queueing, and alerts.
- Build and verify against their sandbox before production.
- Secrets handling, audit logging, and observability of the integration.

## Deliverables
1. Integration architecture and the entity mapping before coding.
2. The complete, runnable integration code with the chosen sync path.
3. A failure/runbook section: outages, replays, and reconciliation.

Proceed with well-reasoned defaults; ask only if blocked.