Add in check_template option

[ghostdevv]

Currently when using svelte-kit package on it's own it fails due to not finding a app.html, this pr makes the package command skip the check for app.html and makes it default for everything else

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🦋 Changeset detected

Latest commit: dc363ee

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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@sveltejs/kit	Patch

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[ghostdevv]

I don't think the netlify tests are failing because of this pr

[Conduitry]

This would resolve #2547.

[ghostdevv]

Awesome, I know you mentioned in that issue that you might not want to encourage users to use svelte kit package standalone - for all my other libs I use it all together but for this particular project the documentation makes more sense being in Routify so I want to use svelte kit package essentially standalone @Conduitry

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[Rich-Harris]

Thank you! Because of this I realised that we're actually doing the validation at the wrong time — in dev, it's possible to start with a valid template, but then make it invalid without raising an error. What we really need to do is validate it at the point of use. I've added a load_template function that dev and build can both use — that way load_config doesn't need to know anything about template validity.

[ghostdevv]

Amazing thank you