## New Packages

### eQuantic.Core.Eventing.Azure
- ServiceBusEventPublisher implementing IExternalEventPublisher
- Batch message support
- Session ID support for FIFO

### eQuantic.Core.Eventing.AWS
- SnsEventPublisher for AWS SNS
- FIFO topic support with MessageGroupId
- Deduplication using EventId

### eQuantic.Core.Eventing.RabbitMQ
- RabbitMqEventPublisher for RabbitMQ
- Exchange/topic routing
- Configurable persistence

### eQuantic.Core.Eventing.Outbox
- IOutboxStore abstraction
- OutboxEventDispatcher for transactional publishing
- OutboxProcessorService background worker
- Guaranteed delivery pattern

## Core Changes
- Added IExternalEventPublisher interface
- Added ExternalEventPublisherOptions base class