fix(sts): return Query API-compatible responses (#5282)

* fix(sts): return Query API-compatible responses

* fix(sts): resolve review and CI failures

* fix(sts): harden query response conversion

* test(e2e): stabilize transition conflict coverage

* fix(ilm): retry vanished transition admission CAS

* test(e2e): narrow transition overlap coverage

---------

Co-authored-by: houseme <housemecn@gmail.com>

crates/ecstore/src/bucket/lifecycle/bucket_lifecycle_ops.rs

@@ -9483,6 +9483,48 @@ mod tests {
         assert_eq!(current.lease_id, second.lease_id);
     }
 
+    #[tokio::test]
+    #[serial]
+    async fn manual_transition_scope_missing_current_is_retryable_cas_miss() {
+        let (_paths, ecstore) = setup_test_env().await;
+        let options = ManualTransitionRunOptions {
+            prefix: "logs/".to_string(),
+            ..Default::default()
+        };
+        let first = ManualTransitionJobRecord::new(Uuid::new_v4(), "manual-replace-race-bucket", &options, "first-owner");
+        save_manual_transition_scope_admission_if_absent(ecstore.clone(), &ManualTransitionScopeAdmission::from_job(&first))
+            .await
+            .expect("first scope admission should save");
+        let (_loaded, etag) = load_manual_transition_scope_admission_with_etag(ecstore.clone(), &first.scope_key)
+            .await
+            .expect("first scope admission should load with an ETag");
+        let object = manual_transition_scope_record_object_name(&first.scope_key).expect("scope admission path should encode");
+        config_boundary::delete_config(ecstore.clone(), &object)
+            .await
+            .expect("current scope admission should be deleted");
+
+        let replacement =
+            ManualTransitionJobRecord::new(Uuid::new_v4(), "manual-replace-race-bucket", &options, "replacement-owner");
+        let stale_replace = save_manual_transition_scope_admission_if_current(
+            ecstore.clone(),
+            &ManualTransitionScopeAdmission::from_job(&replacement),
+            &etag,
+        )
+        .await
+        .expect_err("replacing a disappeared scope admission must report a CAS miss");
+        assert_eq!(stale_replace, Error::PreconditionFailed);
+
+        let claim =
+            claim_manual_transition_scope_admission(ecstore.clone(), &ManualTransitionScopeAdmission::from_job(&replacement))
+                .await
+                .expect("replacement claim should recover through the create path");
+        assert_eq!(claim, ManualTransitionScopeAdmissionClaim::Claimed);
+        let current = load_manual_transition_scope_admission(ecstore, &replacement.scope_key)
+            .await
+            .expect("replacement scope admission should be saved");
+        assert_eq!(current.job_id, replacement.job_id);
+    }
+
     #[tokio::test]
     #[serial]
     async fn manual_transition_admission_reclaims_stale_scope_records() {

crates/ecstore/src/bucket/lifecycle/manual_transition_job.rs

@@ -1466,7 +1466,7 @@ pub async fn save_manual_transition_scope_admission_if_current(
     admission.validate().map_err(manual_transition_job_store_error)?;
     let object = manual_transition_scope_record_object_name(&admission.scope_key).map_err(manual_transition_job_store_error)?;
     let data = serde_json::to_vec(admission).map_err(Error::other)?;
-    config_boundary::save_config_with_opts(
+    match config_boundary::save_config_with_opts(
         api,
         &object,
         data,
@@ -1480,6 +1480,12 @@ pub async fn save_manual_transition_scope_admission_if_current(
         },
     )
     .await
+    {
+        Err(Error::ObjectNotFound(bucket, current_object)) if bucket == RUSTFS_META_BUCKET && current_object == object => {
+            Err(Error::PreconditionFailed)
+        }
+        result => result,
+    }
 }
 
 pub async fn claim_manual_transition_scope_admission(