Stop using hacky features in default theme

[Mister-Hope]

Is your feature request related to a problem? Please describe.

Yes, the default theme has a built-in local search, while it's importing dataSymbol, which is private and not accessable outside vitepress.

vitepress/src/client/theme-default/components/VPLocalSearchBox.vue

Line 30 in 80e734d

import { dataSymbol } from '../../app/data'

By importing this symbol, the built-in local search achieves "mocking pageData in another app instance" and render other page as components.

This is unfair for third party themes, as they do not have same ability to this tricky job and provide a similar built-in theme.

Describe the solution you'd like

Export this symbol or stop using it. The default theme should not access vitepress private apis to "provide magic". Everything should work outside vitepress in order not to embarrass 3rd party themes.

Describe alternatives you've considered

No response

Additional context

No response

Validations

• Follow our Code of Conduct
• Read the docs.
• Read the Contributing Guidelines.
• Check that there isn't already an issue that asks for the same feature to avoid creating a duplicate.

[Mister-Hope]

Special mention the original PR creator and reviewer here: @brc-dd @Akryum