Conflict between legacy KafkaListenerMetrics and Observation-based metrics (spring.kafka.listener_seconds tag mismatch)

[Wolroys]

Description:
In Spring Boot 3.3.x with Spring Kafka 3.3.x, enabling both Actuator metrics and Micrometer Observation causes a Prometheus registration conflict:

Prometheus requires that all meters with the same name have the same set of tag keys.
There is already an existing meter named 'spring.kafka.listener_seconds' containing tag keys [exception, name, result].
The meter you are attempting to register has keys [error, messaging.kafka.consumer.group, messaging.operation, messaging.system, spring.kafka.listener.id].

Steps to reproduce:

Use Spring Boot 3.3.10, Spring Kafka 3.3.10, Actuator, Micrometer, Prometheus.

Enable observation:

spring:
kafka:
listener:
observation-enabled: true

Do not disable Actuator’s default metrics (KafkaMetricsAutoConfiguration).

Run application with at least one @KafkaListener.

Actual result:
Prometheus rejects metric registration due to conflicting tag sets for the same name spring.kafka.listener_seconds.

Expected result:
Observation metrics and legacy metrics should not register under the same metric name. Either:

Observation should use a distinct metric name, or

The framework should automatically suppress legacy KafkaListenerMetrics when observation is enabled.

Environment:

Spring Boot: 3.3.10

Spring Kafka: 3.3.10

Micrometer: 1.13.x

Prometheus Meter Registry

Request:
Provide automatic suppression or name separation for legacy KafkaListenerMetrics when observation-enabled=true, to prevent Prometheus conflicts without manual exclusion.

I've been trying to turn off setMicrometerEnabled through kafkaConfiguration, but it actually hasn't worked