Links to pages outside "base" path scope do not work

[aantipov]

Describe the bug

I have the following site structure

/blog is powered by VitePress (I set base: '/blog/' in /blog/.vitepress/config.js)

The problem is that links from /blog pages to other pages of the website do not work

I checked the console and saw 404 for js bundles. And no document requests

Reproduction

Described above

Expected behavior

Links to pages pages outside /<basePath>/ should work.

As I understood, VitePress treats all the links under / as internal and applies routing and prefetching.
This is the root of the problem.
Scoping routing and prefetching to /<basePath>/ should fix the problem.

Here is where an additional check for basePath is needed for Router
https://github.com/vuejs/vitepress/blob/main/src/client/app/router.ts#L125

Here is where an additional check for basePath is needed for preFetch https://github.com/vuejs/vitepress/blob/main/src/client/app/composables/preFetch.ts#L83

System Info

System:
    OS: macOS 11.6
    CPU: (8) x64 Intel(R) Core(TM) i5-1038NG7 CPU @ 2.00GHz
    Memory: 323.38 MB / 16.00 GB
    Shell: 5.8 - /bin/zsh
  Binaries:
    Node: 16.13.0 - ~/.nvm/versions/node/v16.13.0/bin/node
    Yarn: 1.22.15 - ~/.nvm/versions/node/v16.13.0/bin/yarn
    npm: 8.1.4 - ~/.nvm/versions/node/v16.13.0/bin/npm
  Browsers:
    Brave Browser: 95.1.31.88
    Chrome: 96.0.4664.55
    Firefox: 90.0.2
    Safari: 15.1

Additional context

No response

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[kiaking]

Interesting. Haven't thought about this usage but we might need this.

[brc-dd]

Refer #502 (comment) -- scheme://path is required if linking to any external link (including links outside the base).