fix: per-handler claim lease in ledger, nats max_deliver, pin handler names

crates/adapters/nats/src/config.rs

@@ -11,10 +11,15 @@ pub struct NatsConfig {
     pub subject_prefix: String,
     pub stream_name: String,
     pub consumer_name: String,
+    /// JetStream redelivery bound, same as the DB queue's attempt limit.
+    pub max_deliver: i64,
 }
 
 impl NatsConfig {
-    pub fn from_config(config: &::config::NatsConfig) -> anyhow::Result<Self> {
+    pub fn from_config(
+        config: &::config::NatsConfig,
+        events: &::config::EventsConfig,
+    ) -> anyhow::Result<Self> {
         let url = config
             .url
             .clone()
@@ -32,6 +37,7 @@ impl NatsConfig {
             subject_prefix: config.subject_prefix.clone(),
             stream_name: config.stream_name.clone(),
             consumer_name: config.consumer_name.clone(),
+            max_deliver: i64::from(events.queue_max_attempts),
         })
     }
 }

crates/adapters/nats/src/consumer.rs

@@ -108,8 +108,9 @@ fn consume_from_rx(rx: EnvelopeRx) -> BoxStream<'static, Result<EventEnvelope, D
 
 /// How long JetStream remembers `Nats-Msg-Id`s. A row re-relayed within this
 /// window (crash between publish and mark-done, or a lease reclaim) is dropped
-/// by the broker; beyond it the consumer ledger is the backstop. Set
-/// explicitly so it does not silently follow the server default.
+/// by the broker; a duplicate arriving later is caught by the processed-event
+/// ledger, which keeps its rows for 30 days. Set explicitly so it does not
+/// silently follow the server default.
 const DEDUP_WINDOW: std::time::Duration = std::time::Duration::from_secs(60 * 60);
 
 // ── JetStream consumer ────────────────────────────────────────────────────────
@@ -140,6 +141,7 @@ impl NatsJetStreamConsumer {
                     durable_name: Some(cfg.consumer_name.clone()),
                     filter_subject: subject_filter,
                     ack_wait: std::time::Duration::from_secs(600),
+                    max_deliver: cfg.max_deliver,
                     ..Default::default()
                 },
             )