fix: don't error on dynamic routes with `prerender = false`

[teemingc]

fixes https://github.com/sveltejs/kit/issues/10332

Instead of always erroring on dynamic routes generated with the static adapter, we only error if the prerender option was not explicitly set. This allows users to have dynamic pages in the project but choose to ignore them, which is useful if they have multiple builds that may use a different adapter.

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@sveltejs/adapter-static	Patch

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[dummdidumm]

Is this only about silencing that exact error? What is stopping people from setting the strict: false option? Is that undesireable for some reason? If we go with this solution the error that is otherwise thrown should probably also mention it.

[teemingc]

Is this only about silencing that exact error?

I think it's more about control of whether a route should error if it's not prerendered, which are only some routes but not all routes.

What is stopping people from setting the strict: false option? Is that undesireable for some reason?

I didn't know setting strict: false would disable those prerendering errors 😅 but I think that's undesirable here as it should still error on certain pages that should be prerendered, e.g., those affected by the root layout that sets prerender = true.

If we go with this solution the error that is otherwise thrown should probably also mention it.

I agree. I'll add the information to the error.

[dummdidumm]

Closing, because from what I understand the related issue wouldn't actually be fixed by this, and I'm still not sure we should do this in the first place.