fix: preserve consumer config on update, warn not abort; adr accuracy

crates/adapters/nats/src/consumer.rs

@@ -141,22 +141,20 @@ fn stream_config_update(existing: &StreamConfig) -> Option<StreamConfig> {
 }
 
 /// `Some(updated)` when an existing durable consumer disagrees on `max_deliver`
-/// or `ack_wait`. Both are mutable on a live consumer, so the update is safe
-/// and keeps the consumer's delivery position. Immutable fields (durable name,
-/// filter subject, deliver policy) are never touched.
+/// or `ack_wait`. The update is a clone of the existing config with only those
+/// two fields changed, so operator-set fields survive and immutable ones
+/// (durable name, filter subject, deliver policy) cannot mismatch.
 fn consumer_config_update(
     existing: &jetstream::consumer::Config,
     desired_max_deliver: i64,
-) -> Option<pull::Config> {
+) -> Option<jetstream::consumer::Config> {
     if existing.max_deliver == desired_max_deliver && existing.ack_wait == ACK_WAIT {
         return None;
     }
-    Some(pull::Config {
-        durable_name: existing.durable_name.clone(),
-        filter_subject: existing.filter_subject.clone(),
+    Some(jetstream::consumer::Config {
         ack_wait: ACK_WAIT,
         max_deliver: desired_max_deliver,
-        ..Default::default()
+        ..existing.clone()
     })
 }
 
@@ -185,7 +183,14 @@ impl NatsJetStreamConsumer {
                 "existing JetStream stream has a different duplicate window; updating to {:?}",
                 DEDUP_WINDOW
             );
-            js.update_stream(updated).await?;
+            if let Err(e) = js.update_stream(updated).await {
+                tracing::warn!(
+                    "could not update stream {}: {e}; continuing. Fix manually: nats stream edit {} --dupe-window {}s",
+                    cfg.stream_name,
+                    cfg.stream_name,
+                    DEDUP_WINDOW.as_secs()
+                );
+            }
         }
 
         let subject_filter = consumer_subject_filter(&cfg.subject_prefix);
@@ -209,7 +214,15 @@ impl NatsJetStreamConsumer {
                 "existing JetStream consumer has different max_deliver/ack_wait; updating to max_deliver={}",
                 cfg.max_deliver
             );
-            stream.update_consumer(updated).await?;
+            if let Err(e) = stream.update_consumer(updated).await {
+                tracing::warn!(
+                    "could not update consumer {}: {e}; continuing. Fix manually: nats consumer edit {} {} --max-deliver {}",
+                    cfg.consumer_name,
+                    cfg.stream_name,
+                    cfg.consumer_name,
+                    cfg.max_deliver
+                );
+            }
         }
 
         let (tx, rx) = mpsc::channel(128);

crates/adapters/nats/src/tests/consumer.rs

@@ -75,12 +75,16 @@ fn consumer_max_deliver_drift_is_updated() {
         filter_subject: "a.>".into(),
         max_deliver: -1,
         ack_wait: ACK_WAIT,
+        max_ack_pending: 77,
+        description: Some("operator".into()),
         ..Default::default()
     };
     let updated = consumer_config_update(&existing, 5).unwrap();
     assert_eq!(updated.max_deliver, 5);
     assert_eq!(updated.durable_name.as_deref(), Some("c"));
     assert_eq!(updated.filter_subject, "a.>");
+    assert_eq!(updated.max_ack_pending, 77);
+    assert_eq!(updated.description.as_deref(), Some("operator"));
     let same = jetstream::consumer::Config {
         max_deliver: 5,
         ..existing