test(admin): pin minio-go Metrics/MetricsV2 wire contract for replication metrics

Red-light evidence for backlog#1675 P1-11: ?replication-metrics[=2]
serializes the internal snake_case BucketStats family straight onto the
wire, while minio-go's replication.Metrics/MetricsV2 expect camelCase
tags (currStats/queueStats/replicaCount/queued/...). Go's decoder is
case-insensitive but does not ignore underscores, so 'mc replicate
status' shows all zeros without any error. The rewritten snapshot tests
assert the minio-go tags (plus a synthesized queueStats node — the
aggregation path leaves queue_stats.nodes empty today) and fail against
the current pass-through serialization.

rustfs/src/admin/router.rs

@@ -4147,22 +4147,37 @@ mod tests {
         assert!(err.message().unwrap_or_default().contains("rule-stale"));
     }
 
+    /// The v1 body must decode into minio-go `replication.Metrics` (exact
+    /// json tags); Go's decoder matches case-insensitively but does not
+    /// ignore underscores, so the internal snake_case names read as all-zero.
     #[test]
-    fn serialize_replication_metrics_body_v1_returns_replication_stats_only() {
+    fn serialize_replication_metrics_body_v1_returns_minio_go_metrics_shape() {
         let mut stats = BucketStats {
             uptime: 99,
             ..Default::default()
         };
         stats.replication_stats.replica_count = 7;
+        stats.replication_stats.replicated_size = 2048;
+        stats
+            .replication_stats
+            .stats
+            .entry("arn:minio:replication::t:b".to_string())
+            .or_default()
+            .replicated_count = 5;
         stats.proxy_stats.put_total = 3;
 
         let body =
             serialize_replication_metrics_body(&stats, ReplicationExtRoute::MetricsV1).expect("metrics v1 body should serialize");
         let payload: serde_json::Value = serde_json::from_slice(&body).expect("body should be json");
 
-        assert_eq!(payload["replica_count"], 7);
+        assert_eq!(payload["replicaCount"], 7);
+        assert_eq!(payload["completedReplicationSize"], 2048);
+        assert_eq!(payload["Stats"]["arn:minio:replication::t:b"]["replicationCount"], 5);
         assert!(payload.get("uptime").is_none());
         assert!(payload.get("proxy_stats").is_none());
+        // The internal snake_case names must not leak into the wire body.
+        assert!(payload.get("replica_count").is_none());
+        assert!(payload.get("q_stat").is_none());
     }
 
     #[test]
@@ -4248,13 +4263,30 @@ mod tests {
         assert_eq!(target.current_bandwidth_bytes_per_sec, 3000.0);
     }
 
+    /// The v2 body must decode into minio-go `replication.MetricsV2`
+    /// (`uptime`/`currStats`/`queueStats`); `mc replicate status` reads
+    /// `currStats` and `queueStats.nodes` and silently shows zeros when the
+    /// keys do not match.
     #[test]
-    fn serialize_replication_metrics_body_v2_returns_full_bucket_stats() {
+    fn serialize_replication_metrics_body_v2_returns_minio_go_metrics_v2_shape() {
         let mut stats = BucketStats {
             uptime: 99,
             ..Default::default()
         };
         stats.replication_stats.replica_count = 7;
+        stats
+            .replication_stats
+            .q_stat
+            .curr
+            .now_count
+            .store(4, std::sync::atomic::Ordering::Relaxed);
+        stats
+            .replication_stats
+            .q_stat
+            .curr
+            .now_bytes
+            .store(1200, std::sync::atomic::Ordering::Relaxed);
+        stats.replication_stats.q_stat = stats.replication_stats.q_stat.snapshot();
         stats.proxy_stats.put_total = 3;
 
         let body =
@@ -4262,8 +4294,17 @@ mod tests {
         let payload: serde_json::Value = serde_json::from_slice(&body).expect("body should be json");
 
         assert_eq!(payload["uptime"], 99);
-        assert_eq!(payload["replication_stats"]["replica_count"], 7);
-        assert_eq!(payload["proxy_stats"]["put_total"], 3);
+        assert_eq!(payload["currStats"]["replicaCount"], 7);
+        assert_eq!(payload["currStats"]["queued"]["curr"]["count"], 4.0);
+        // The queue snapshot must surface at least one node: mc derives the
+        // worker/queue panels from queueStats.nodes and treats an empty list
+        // as "no data".
+        assert_eq!(payload["queueStats"]["nodes"][0]["queueStats"]["curr"]["count"], 4.0);
+        assert_eq!(payload["queueStats"]["nodes"][0]["uptime"], 99);
+        // The internal snake_case names must not leak into the wire body.
+        assert!(payload.get("replication_stats").is_none());
+        assert!(payload.get("queue_stats").is_none());
+        assert!(payload.get("proxy_stats").is_none());
     }
 
     #[test]