Add a way to get Deno.emit to emit formatted code

[jaydenseric]

At the moment, Deno.emit outputs messy code, that is not in the same format that Deno fmt produces.

Either by default, or as a new option, it would be great if there was a way to get Deno.emit to emit formatted code that is accounted for in the source maps that are also emitted.

Until this enhancement is implemented a workaround is a bit tricky. Unfortunately there is not a runtime API yet for fmt, see: denoland/deno#10731 . So you would need to use the fmt CLI somehow in a child process? That's something I haven't done yet in Deno. Would there be a way to get the source map to include the changes made by the fmt CLI?