[Perf]: The version and languages in nav may be optimized

### What problem does this perf solve?

[packages/theme-default/src/components/Nav/menuDataHooks.tsx](https://github.com/web-infra-dev/rspress/blob/main/packages/theme-default/src/components/Nav/menuDataHooks.tsx)
I found that there are many duplicate parts in two of the code segments, especially the `replaceVersion` and `replaceLang` functions. Perhaps they can be optimized?