Feature request

What problem does this feature solve?

Internationalization in VuePress is nice, easy to use and understand but I can't find any way to manage the "Internationalization coverage".

Let's show an example,
Today we finish to translate all the docs to French (french coverage 100%)
Tomorrow someone update or add a new file at the base docs.
The french version becomes inacurate, outdated or incomplete

I think it should be nice has an alert when an Internationalization need to be updated.

What does the proposed API look like?

maybe during the dev build verify if exist internationalizations and show some warnings like:

• file "X" in (languaje) need to be updated
• file "Y" is not translate to (languaje)
• (count) of files are translate to (languaje), your coverage in (languaje) is %

How should this be implemented in your opinion?

I think is possible to use the commits.

The translations should be done after the base language files are write.
The vuepress guide show to keep the same file name in the other languajes as a good practice so maybe it's possible use this info to validate if a file in a translation languaje was commited after to the last change of the same file in the base languaje.
Same for the coverage, verify if all files appears in a translation language.

Are you willing to work on this yourself?

not sure