request help: How to route according to the configuration of nacos metadata?

### Issue description

I use nacos discovery, and for each microservice I register some additional metadata for finer-grained control

I know that the traffic-split plugin can match routes at a certain level of granularity
As far as I know, this plugin can't match upstreams based on metadata level

So, I would like to ask how to do this

Tks

### Environment

- apisix 2.10.2
- Centos7
- openresty/1.19.3.2
- etcd 3.5.0

Start with the Nacos discovery integration and the traffic-split plugin, using the reported APISIX 2.10.2 environment as context. Determine whether routing by Nacos service metadata is an existing configuration capability or requires a new feature; the issue does not identify files, tests, or a concrete completion condition.

Written by the indexing model from the issue text.