Support composable docs.json file

[Blargian]

What is the current behavior?

At the moment everything needs to be defined inside a single docs.json file. Take for example the docs.json file for the Mintlify docs: https://github.com/mintlify/docs/blob/main/docs.json which has multiple languages and redirects.

How could it improve?

It would be cool if there was a way to pull-in definitions stored in other json files. For example if you could have separate docs-ja.json, docs-ko.json, docs-ru.json files for languages or a redirects.json for redirects. You could then just specify the relative path to those files in docs.json, for example something like:

"navigation": {
    "languages": [
        {"path": "../docs-kr.json"},
        {"path": "../docs-ru.json"},
        {"path": "../docs-ja.json"}
]
},
"redirects": "../redirects.json"

Why is this worth implementing?

Having the ability to split up docs.json allows for easier parsing of the file as a human and it separates concerns.
Additionally, Docusaurus supports this in docusaurus.config.js.
Fern also partially supports this, at least with regards to navigation. It's possible on their platform to have multiple .yml files defining the navigation and to import them into the parent "docs.json" equivalent.

In both cases it is a substantial quality of life improvement imo.