fix(daemon): add shutdown grace window and signal hint parity

(cherry picked from commit 61cc0aad34)

src/daemon/mod.rs

@@ -7,6 +7,7 @@ use tokio::task::JoinHandle;
 use tokio::time::Duration;
 
 const STATUS_FLUSH_SECONDS: u64 = 5;
+const SHUTDOWN_GRACE_SECONDS: u64 = 5;
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 enum ShutdownSignal {
@@ -21,6 +22,16 @@ fn shutdown_reason(signal: ShutdownSignal) -> &'static str {
     }
 }
 
+#[cfg(unix)]
+fn shutdown_hint() -> &'static str {
+    "Ctrl+C or SIGTERM to stop"
+}
+
+#[cfg(not(unix))]
+fn shutdown_hint() -> &'static str {
+    "Ctrl+C to stop"
+}
+
 async fn wait_for_shutdown_signal() -> Result<ShutdownSignal> {
     #[cfg(unix)]
     {
@@ -32,7 +43,10 @@ async fn wait_for_shutdown_signal() -> Result<ShutdownSignal> {
                 ctrl_c?;
                 Ok(ShutdownSignal::CtrlC)
             }
-            _ = sigterm.recv() => Ok(ShutdownSignal::SigTerm),
+            sigterm_result = sigterm.recv() => match sigterm_result {
+                Some(()) => Ok(ShutdownSignal::SigTerm),
+                None => bail!("SIGTERM signal stream unexpectedly closed"),
+            },
         }
     }
     #[cfg(not(unix))]
@@ -124,19 +138,40 @@ pub async fn run(config: Config, host: String, port: u16) -> Result<()> {
     println!("🧠 ZeroClaw daemon started");
     println!("   Gateway:  http://{host}:{port}");
     println!("   Components: gateway, channels, heartbeat, scheduler");
-    println!("   Ctrl+C or SIGTERM to stop");
+    println!("   {}", shutdown_hint());
 
     let signal = wait_for_shutdown_signal().await?;
     crate::health::mark_component_error("daemon", shutdown_reason(signal));
+    let aborted =
+        shutdown_handles_with_grace(handles, Duration::from_secs(SHUTDOWN_GRACE_SECONDS)).await;
+    if aborted > 0 {
+        tracing::warn!(
+            aborted,
+            grace_seconds = SHUTDOWN_GRACE_SECONDS,
+            "Forced shutdown for daemon tasks that exceeded graceful drain window"
+        );
+    }
 
+    Ok(())
+}
+
+async fn shutdown_handles_with_grace(handles: Vec<JoinHandle<()>>, grace: Duration) -> usize {
+    let deadline = tokio::time::Instant::now() + grace;
+    while !handles.iter().all(JoinHandle::is_finished) && tokio::time::Instant::now() < deadline {
+        tokio::time::sleep(Duration::from_millis(50)).await;
+    }
+
+    let mut aborted = 0usize;
     for handle in &handles {
-        handle.abort();
+        if !handle.is_finished() {
+            handle.abort();
+            aborted += 1;
+        }
     }
     for handle in handles {
         let _ = handle.await;
     }
-
-    Ok(())
+    aborted
 }
 
 pub fn state_file_path(config: &Config) -> PathBuf {
@@ -400,6 +435,38 @@ mod tests {
         );
     }
 
+    #[test]
+    fn shutdown_hint_matches_platform_signal_support() {
+        #[cfg(unix)]
+        assert_eq!(shutdown_hint(), "Ctrl+C or SIGTERM to stop");
+
+        #[cfg(not(unix))]
+        assert_eq!(shutdown_hint(), "Ctrl+C to stop");
+    }
+
+    #[tokio::test]
+    async fn graceful_shutdown_waits_for_completed_handles_without_abort() {
+        let finished = tokio::spawn(async {});
+        let aborted = shutdown_handles_with_grace(vec![finished], Duration::from_millis(20)).await;
+        assert_eq!(aborted, 0);
+    }
+
+    #[tokio::test]
+    async fn graceful_shutdown_aborts_stuck_handles_after_timeout() {
+        let never_finishes = tokio::spawn(async {
+            tokio::time::sleep(Duration::from_secs(30)).await;
+        });
+        let started = tokio::time::Instant::now();
+        let aborted =
+            shutdown_handles_with_grace(vec![never_finishes], Duration::from_millis(20)).await;
+
+        assert_eq!(aborted, 1);
+        assert!(
+            started.elapsed() < Duration::from_secs(2),
+            "shutdown should not block indefinitely"
+        );
+    }
+
     #[tokio::test]
     async fn supervisor_marks_error_and_restart_on_failure() {
         let handle = spawn_component_supervisor("daemon-test-fail", 1, 1, || async {