❔ ASP.NET Core reroute requests for static files to a different server

This is supposed to be implemented by Microsoft.AspNetCore.SpaServices.Extensions, like this guy does here https://github.com/MakotoAtsu/AspNetCore_Vite_Template
However there's an issue: I want a) to be able to start the server separately, b) to use the manifest generated by Vite to provide the files.

The code in the template above doesn't actually work as I need it to: it looks at the dist folder to get the available files, while what should actually happen is it should read in the manifest file generated by vite, which remaps the files correctly and whatnot. So I need a custom FileProvider. The problem with that is the method GetFileInfo, which returns an IFileInfo, which has to implement CreateReadStream(), which I have no idea why aspnet core needs in the first place, and I don't know how to implement it myself. The implementations provided by aspnet core deal with actual files on disk or embedded resources, but not files streamed over http, so idk what to do.