add package script, change behaviour of build script

[Rich-Harris]

closes #8240

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🦋 Changeset detected

Latest commit: 4f614bc

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

This PR includes changesets to release 1 package

Name	Type
create-svelte	Major

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[gtm-nayan]

IIRC svelte-package doesn't do checking and svelte-check isn't included in the library template so the generated types go unused. svelte-check and a check command should probably be added in as well esp with #8484 merged.

[Rich-Harris]

Good point. I wonder if we should try and make svelte-check only apply to packaged files rather than the entire app — would be annoying if you couldn't publish because of a finicky type error in your docs site that you don't really care about

[dummdidumm]

For that we could create a tsconfig.lib.json which only includes the files inside lib and reference that from svelte-check

[Rich-Harris]

feels a bit messy to create a new file, and if config.kit.files.lib changed the developer would also need to change tsconfig.lib.json... perhaps there's a way to integrate checking into the svelte-package command instead?

[dummdidumm]

Closing in favor of #8922 (which will also make this change)