feat: Implement graceful shutdown and enhanced job recovery

- Added shutdown handler in docker-entrypoint.sh to manage application termination signals.
- Introduced shutdown manager to track active jobs and ensure state persistence during shutdown.
- Enhanced cleanup service to support stopping and status retrieval.
- Integrated signal handlers for proper response to termination signals (SIGTERM, SIGINT, SIGHUP).
- Updated middleware to initialize shutdown manager and cleanup service.
- Created integration tests for graceful shutdown functionality, verifying job state preservation and recovery.
- Documented graceful shutdown process and configuration in GRACEFUL_SHUTDOWN.md and SHUTDOWN_PROCESS.md.
- Added new scripts for testing shutdown behavior and cleanup.

package.json

@@ -22,6 +22,8 @@
     "startup-recovery-force": "bun scripts/startup-recovery.ts --force",
     "test-recovery": "bun scripts/test-recovery.ts",
     "test-recovery-cleanup": "bun scripts/test-recovery.ts --cleanup",
+    "test-shutdown": "bun scripts/test-graceful-shutdown.ts",
+    "test-shutdown-cleanup": "bun scripts/test-graceful-shutdown.ts --cleanup",
     "preview": "bunx --bun astro preview",
     "start": "bun dist/server/entry.mjs",
     "start:fresh": "bun run cleanup-db && bun run manage-db init && bun run update-db && bun dist/server/entry.mjs",