Support and documentation for GitHub Enterprise

I've not been able to find much documentation on [this page](https://docs.github.com/en/repositories/working-with-files/using-files/navigating-code-on-github) or in this repository about the state of GitHub Enterprise support.

If it is supported, what is needed to enable it? If it is not supported, can we get support for it?

Start with the linked GitHub documentation page and inspect this repository for existing references to GitHub Enterprise. Establish whether Enterprise is supported and, if so, what enables it; document the confirmed status and setup guidance, or clarify the missing support work.

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