turbopack: defer dev code evaluation until after page render IPC connects (#47888)
When the devs have a parse/module-eval error in their Page/App module, Turbopack's rendering process will fail to connect the IPC. This is because the entrypoint statically imports the dev module. If either fails, then we'll never reach the code to set up the IPC. This leads to a "timeout while receiving message from process" timeout error after 30s, instead of receiving an exact message/stack detailing the dev's error.
By wrapping the import code in a deferred dynamic-import closure, we're able to connect the IPC first, then evaluate the dev code. This wrapping style is a little awkward, but it's necessary with the way to inject virtual modules into our graph.
Fixes WEB-850