🪐 feat: Cross-replica support in GenerationJobManager for Redis mode (#11233)

* feat: Implement cross-replica support in GenerationJobManager for Redis mode

- Enhanced GenerationJobManager to support cross-replica scenarios by lazily creating runtime states from Redis when jobs exist but are not present in local memory.
- Added functionality to persist `syncSent` and `finalEvent` states to Redis for consistency across replicas.
- Implemented abort signal handling to allow replicas to receive and respond to abort requests from other instances, ensuring proper job termination.
- Updated tests to validate cross-replica behavior, including job retrieval, subscription, and abort signal propagation.

This update improves the robustness and reliability of job management in distributed environments.

* fix: Enhance error handling and implement abort signal for cross-replica jobs in GenerationJobManager

- Added error handling for Redis job updates in GenerationJobManager to log failures when persisting `syncSent` and `finalEvent` states.
- Implemented a listener for cross-replica abort signals, ensuring that lazily-initialized jobs can respond to abort requests from other replicas.
- Introduced a new integration test to validate the handling of abort signals for lazily-initialized jobs across replicas.

These changes improve the reliability and robustness of job management in distributed environments.

packages/api/src/stream/interfaces/IJobStore.ts

@@ -236,6 +236,21 @@ export interface IEventTransport {
   /** Publish an error event */
   emitError(streamId: string, error: string): void;
 
+  /**
+   * Publish an abort signal to all replicas (Redis mode).
+   * Enables cross-replica abort: user aborts on Replica B,
+   * generating Replica A receives signal and stops.
+   * Optional - only implemented in Redis transport.
+   */
+  emitAbort?(streamId: string): void;
+
+  /**
+   * Register callback for abort signals from any replica (Redis mode).
+   * Called when abort is triggered from any replica.
+   * Optional - only implemented in Redis transport.
+   */
+  onAbort?(streamId: string, callback: () => void): void;
+
   /** Get subscriber count for a stream */
   getSubscriberCount(streamId: string): number;