Reduce blueprint variance and *always* have typescript support by default.

[NullVoxPopuli]

Like with Vite, Bun, Deno, ESBuild, Parcel, RSpack, etc, I think we should always support typescript as an output, rather than have two varying blueprint outputs / branches.

What's great is that even if someone doesn't like typescript, none of the typescript stuff actually gets in their way, and they can use JS / GJS just fine.

This has the added advantage tho of enabling Glint by default, which there is an RFC for, and would also require a configured tsconfig.json anyway in JS projects.

Now, maybe we keep the --typescript flag and add / remove the lint:types script, and that's it, keeping everything else the same.

Thoughts?