Operator throws "unable to scale down number of partition in topic" error

I created a simple topic:

apiVersion: cluster.redpanda.com/v1alpha2
kind: Topic
metadata:
  name: test
  namespace: redpanda
spec:
  additionalConfig:
    cleanup.policy: compact
  cluster:
    clusterRef:
      name: redpanda

The events of the created topic ressource:

Events:                                                                                                                             
  Type     Reason                             Age                     From             Message                                      
  ----     ------                             ----                    ----             -------                                      
  Warning  topicConfigurationDescribeFailure  8m43s                   TopicReconciler  describing topic configuration ([UNKNOWN_TOPIC_OR_PARTITION: This server does not host this topic-partition.[]) DescribeConfigsResponse error (%!!(MISSING)s(MISSING)): %!!(MISSING)s(MISSING)                                                                                                                        
  Warning  topicConfigurationDescribeFailure  3m15s (x17 over 8m43s)  TopicReconciler  unable to update topic ([unable to scale down number of partition in topic[]): %!!(MISSING)s(MISSING) 

Operator log:

{"level":"error","ts":"2025-10-01T20:30:37.818Z","logger":"TopicReconciler.Reconcile","msg":"failed to reconcile","controller":"topic","controllerGroup":"cluster.redpanda.com","controllerKind":"Topic","Topic":{"name":"test","namespace":"redpanda"},"namespace":"redpanda","name":"test","reconcileID":"2fd0de29-b358-43af-b84d-bcc4dd2372f9","topic":{"apiVersion":"cluster.redpanda.com/v1alpha2","kind":"Topic","namespace":"redpanda","name":"test"},"error":"unable to update topic (test): unable to scale down number of partition in topic"}                                                                                                                                                                                
{"level":"error","ts":"2025-10-01T20:30:37.818Z","msg":"Reconciler error","controller":"topic","controllerGroup":"cluster.redpanda.com","controllerKind":"Topic","Topic":{"name":"test","namespace":"redpanda"},"namespace":"redpanda","name":"test","reconcileID":"2fd0de29-b358-43af-b84d-bcc4dd2372f9","error":"unable to update topic (test): unable to scale down number of partition in topic"}

In any case, the functionality of the topic itself does not appear to be affected, which is why I am not entirely sure whether this can be considered a "bug".

However, as I can imagine that this could quickly become an unnecessary workload for the operator with a large number of topics, I thought it would be worth creating an issue.

P.S.: I promise it's my last issue (for today). 😆

Start by reproducing the issue with the provided Topic manifest and inspect the TopicReconciler reconcile path that emits the topicConfigurationDescribeFailure event. Trace the update and partition-scaling errors in the operator logs, then verify that reconciliation no longer repeats the error for a newly created topic.