Redis stats: extract Redis command as Prometheus label in metrics

Title: Extract Redis Command as Prometheus Label in Metrics

Description: Currently, Redis Prometheus metrics are using the metric name to identify which Redis command is being measured. This makes it difficult to filter and aggregate metrics by command, which is a common use case for monitoring Redis performance.

Redis metrics could be improved by extracting the Redis command name as a Prometheus label (tag), as recommended by Prometheus best practices. This would allow users to easily filter and aggregate metrics by command.

For example, instead of the metric name envoy_redis_command_mset_total for the mset command, the metric could be labeled as envoy_redis_command_total{command="mset"}.

Thank you for considering this feature request.