fix(client): remove obsolete device-registry cleanup task

src/client/device_registry.rs

@@ -988,18 +988,6 @@ impl Client {
         devices
     }
 
-    /// Background loop placeholder for device registry cleanup.
-    /// Note: Cleanup functionality was removed as part of trait simplification.
-    /// Device registry entries are managed through normal update/get operations.
-    pub(super) async fn device_registry_cleanup_loop(&self) {
-        // Simply wait for shutdown signal
-        self.shutdown_notifier.listen().await;
-        debug!(
-            target: "Client/DeviceRegistry",
-            "Shutdown signaled, exiting cleanup loop"
-        );
-    }
-
     /// Migrate device registry entries from PN key to LID key.
     #[cfg_attr(
         feature = "tracing",

src/client/lifecycle.rs

@@ -313,14 +313,6 @@ impl Client {
             }))
             .detach();
 
-        // Start background task to clean up stale device registry entries
-        let cleanup_arc = arc.clone();
-        arc.runtime
-            .spawn(Box::pin(async move {
-                cleanup_arc.device_registry_cleanup_loop().await;
-            }))
-            .detach();
-
         (arc, rx)
     }
 

src/client/tests.rs

@@ -3409,6 +3409,28 @@ async fn terminal_disconnect_propagates_to_per_connection_signal() {
     );
 }
 
+/// Dropping the last owner must release persistence handles promptly.
+#[tokio::test]
+async fn dropping_fresh_client_releases_it_without_shutdown() {
+    let client = crate::test_utils::create_test_client().await;
+    let weak = Arc::downgrade(&client);
+
+    drop(client);
+
+    tokio::time::timeout(Duration::from_secs(5), async {
+        while weak.strong_count() != 0 {
+            tokio::task::yield_now().await;
+        }
+    })
+    .await
+    .unwrap_or_else(|_| {
+        panic!(
+            "client is still retained by a background task (strong_count={})",
+            weak.strong_count()
+        )
+    });
+}
+
 /// Locks the zero-allocation property of the ack miss path: id resolution and
 /// the waiter probe must borrow from the node buffer. An `into_owned()` here
 /// costs one String per received ack, which the e2e dhat profile caught live.