glm-5.1
78a518acd4
Implement signal handling and graceful shutdown
- Add GracefulShutdown struct with watch channel for shutdown signaling
- Handle SIGTERM/SIGINT via signal-hook to trigger graceful shutdown
- Handle SIGHUP via signal-hook for config reload (same code path as admin socket)
- Implement graceful shutdown sequence: stop accepting -> drain -> force-close -> cancel tasks -> exit 0
- Wire up main.rs with full server startup (health check, admin socket, HTTP redirect, HTTPS proxy)
- Add integration tests for GracefulShutdown and SIGHUP reload
- shutdown_timeout_secs configurable in StaticConfig (default 30)