chore(deploy): add compose runtime stack

.env.sample

@@ -0,0 +1,12 @@
+POSTGRES_DB=job_queue
+POSTGRES_USER=postgres
+POSTGRES_PASSWORD=postgres
+POSTGRES_PORT=5432
+JOB_WORKER_THREADS=4
+JOB_WORKER_POLL_INTERVAL_MS=500
+JOB_WORKER_LEASE_SECONDS=30
+JOB_WORKER_CLEANUP_INTERVAL_SECONDS=5
+JOB_WORKER_CLEANUP_BATCH_SIZE=100
+JOB_WORKER_BACKOFF_BASE_SECONDS=5
+JOB_WORKER_BACKOFF_MAX_SECONDS=300
+JOB_WORKER_MAX_ATTEMPTS_DEFAULT=3