feat(core-testing): RecordingJobQueue

Adds RecordingJobQueue implementing IJobQueue for use in unit tests.
Records all enqueue calls with taskSlug/input/options and returns
synthetic incrementing jobIds.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/core-testing/src/instrumentation/recording-job-queue.ts

@@ -0,0 +1,14 @@
+import type { IJobQueue } from "@repo/core-shared/jobs";
+
+export class RecordingJobQueue implements IJobQueue {
+  readonly enqueued: { taskSlug: string; input: unknown; options?: { runAt?: Date } }[] = [];
+
+  async enqueue<T>(
+    taskSlug: string,
+    input: T,
+    options?: { runAt?: Date },
+  ): Promise<{ jobId: string }> {
+    this.enqueued.push({ taskSlug, input, options });
+    return { jobId: `recording-${this.enqueued.length}` };
+  }
+}