[Feature] External Orchestration Service

[yedidyakfir]

Description

Create the external service that consumes status events and triggers callbacks.

Blocked by: #44, #45, #46

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Components

1. Event Consumer: Redis Streams consumer with consumer group
2. Event Processor: Idempotent callback activation
3. Recovery Handler: Startup scan for incomplete activations
4. Dead Letter Handler: Failed event management
5. Health Check: Monitoring endpoint

Tech Stack

• Async Python (asyncio)
• Rapyer for Redis models
• Redis Streams for events

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Tasks

• Set up service scaffold
• Implement event consumer loop
• Implement idempotent event processing
• Add startup recovery scan
• Add dead letter queue handling
• Add health check and metrics
• Create Dockerfile