update generated tsconfig

[ghostdevv]

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It's probably best to discuss the side effects of this change, it fixes my issue of #4460 and also #4764 - However this was changed in #4633 and maybe this change is what should stay and alternative solution to the issues can be done such as what I proposed here #4460 (comment)

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🦋 Changeset detected

Latest commit: 2d3bd52

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@sveltejs/kit	Patch

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[Conduitry]

Maybe we should be using esnext as the target for all of these things? We don't want to output CJS, but we also want to make people opt in to whatever specific degree of JS transpiling they need for their situation.

[ghostdevv]

Good idea, have switched to that

[Rich-Harris]

Thanks, this seems like the right fix to me