Expose module resolution code in a public library (like deno_runtime)

[ranile]

I attempted to embed Deno in a Rust app to serve a server-rendered web page from JS framework (SvelteKit) as part of a Rust web server. deno_runtime::worker::MainWorker need a module loader, which the CLI provides (https://github.com/denoland/deno/blob/main/cli/module_loader.rs), however it is not exported.

The desire for this has been brought up before (#21968, https://questions.deno.com/m/1204794589064462346, #9595)
It would be nice if module loader (and worker lifecycle) could be extracted into separate published crates like runtime and core are.