Language preferences are not preserved

Describe the bug

https://github.com/antfu/vitesse/assets/38343778/ec6c2832-eb59-4f59-b915-399c19b48788

As you can see in the video, I switched the colour theme to bright colours, as well as switching the language

And then refreshed the page

After that, the colour theme is still bright, but the language is back to English

So, I think we should make the language preference persistent in the browser as well

Reproduction

https://vitesse.netlify.app/

System Info

System:
    OS: macOS 14.0
    CPU: (8) x64 Intel(R) Core(TM) i7-1068NG7 CPU @ 2.30GHz
    Memory: 681.03 MB / 32.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 16.16.0 - ~/.nvm/versions/node/v16.16.0/bin/node
    Yarn: 1.22.18 - /usr/local/bin/yarn
    npm: 9.8.1 - ~/.nvm/versions/node/v16.16.0/bin/npm
    pnpm: 8.6.12 - ~/.nvm/versions/node/v16.16.0/bin/pnpm
  Browsers:
    Chrome: 118.0.5993.117
    Safari: 17.0

Used Package Manager

pnpm

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