Gate usage of --module/--moduleResolution node12/nodenext on nightly releases

[DanielRosenwasser]

In #46452 and #46453, we came to the conclusion that the nodenext and node12 settings for module and moduleResolution should not ship in TypeScript 4.5, and should instead be gated on nightly releases.

In a beta/rc/insiders/stable (or really, any non-dev) release

• tsc should error on this flag combination
• API users should get a diagnostic in program construction

One possible error message would be:

The '{0}' compiler option can only be set to '{1}' on nightly TypeScript releases. Learn more at: https://www.typescriptlang.org/docs/handbook/nightly-builds.html

another might be

The '{0}' compiler option can only be set to '{1}' on nightly TypeScript releases. Try updating with 'npm install -D typescript@next'.

One thing that's still a little fuzzy - I think .mts/.mjs/.cts/.cjs should be passively allowed in editing; but should they be errors to include within a compilation? Is it possible to make that distinction today?

[weswigham]

I think .mts/.mjs/.cts/.cjs should be passively allowed in editing; but should they be errors to include within a compilation?

I don't think that's a category of error we make right now - that'd be, like, what, an anti-suggestion? (Since suggestions are editor only). It's probably possible, but unlike the nightly-only option, I don't think we have much in place to actually make that possible yet, so it'd need a bit of work. But anyways, I don't see much of an issue allowing them in the old module modes, compilation or no, since we treat them the same as other input files in them (except for retaining extension associations, ofc). Maybe we'd add a suggestion in them to set the newer module mode, if/where/once available? I don't think we'd break anything about how they're handled in old modes, anyway.