dubbo 2.7.x+ 版本关闭元数据中心功能

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如题，对元数据中心功能无需求，是否可以关闭？

Start by reading the Dubbo 2.7.x documentation and configuration paths for the metadata center, then trace where that feature is initialized. Determine whether disabling it is supported and what configuration or behavioral changes would be required; done should be a documented, verified answer or a clearly scoped implementation request.

Written by the indexing model from the issue text.