fix: defer blocked deliveries, claim owner token

crates/adapters/sqlite/src/event_queue/mod.rs

@@ -259,6 +259,22 @@ impl AckHandle for DbAckHandle {
         }
         Ok(())
     }
+
+    async fn defer(&self, delay: std::time::Duration) -> Result<(), DomainError> {
+        let secs = delay.as_secs_f64().ceil().max(1.0) as i64;
+        let sql = format!(
+            "UPDATE event_queue
+             SET status = 'pending', claimed_at = NULL, last_error = 'deferred',
+                 next_attempt_at = strftime('%Y-%m-%dT%H:%M:%SZ', 'now', '+{secs} seconds')
+             WHERE id = ?"
+        );
+        sqlx::query(&sql)
+            .bind(self.row_id)
+            .execute(&self.pool)
+            .await
+            .map_err(|e| DomainError::InfrastructureError(format!("defer: {e}")))?;
+        Ok(())
+    }
 }
 
 fn backoff_seconds(attempts: i32) -> i64 {

crates/adapters/sqlite/src/event_queue/tests.rs

@@ -189,6 +189,33 @@ mod identity {
 
         assert!(envelope.id().is_none());
     }
+
+    #[tokio::test]
+    async fn defer_reschedules_without_counting_an_attempt() {
+        let (q, pool) = queue().await;
+        q.publish(&event()).await.unwrap();
+        let envelope = q.consume().next().await.unwrap().unwrap();
+
+        envelope
+            .defer(std::time::Duration::from_secs(600))
+            .await
+            .unwrap();
+
+        let (status, attempts, claimed, due_in): (String, i32, Option<String>, i64) =
+            sqlx::query_as(
+                "SELECT status, attempts, claimed_at,
+                        CAST(strftime('%s', next_attempt_at) AS INTEGER)
+                          - CAST(strftime('%s', 'now') AS INTEGER)
+                 FROM event_queue",
+            )
+            .fetch_one(&pool)
+            .await
+            .unwrap();
+        assert_eq!(status, "pending");
+        assert_eq!(attempts, 0, "a deferral is not a failed attempt");
+        assert!(claimed.is_none(), "claim is released");
+        assert!((595..=600).contains(&due_in), "due in {due_in}s");
+    }
 }
 
 mod lease {