* Compile pages to .next/static/<buildid>/pages/<page>
* Fix test
* Export class instead of using exports
* Use constant for static directory
* Add comment about what the middleware does
Previously we called this directory holding the pages/chunks for server rendering `.next/dist` instead of `.next/server` which is confusing both when looking at it and in the codebase, since there's also `distDir` as a configuration option.
Also made this a constant in `next/constants` so functionality using this can be easily found.