feat: support specifying the tsconfig in svelte-package

[quentinderoubaix]

closes #9373

Adds the option tsconfig to svelte-package, allowing to specify which tsconfig / jsconfig to use during the packaging.

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[benmccann]

I don't understand why this is necessary or why it would apply only to svelte package

[quentinderoubaix]

I don't understand why this is necessary or why it would apply only to svelte package

Hi @benmccann, thanks for checking this PR !

In the context of a monorepo where two svelte libraries coexist, (example of a headless widget library and a styled widget library depending on the headless), I would like to be able to have aliases in the default tsconfig.json, to navigate easier in the code in my IDE.
However, if I create aliases directly in the tsconfig.json, svelte-package seems to add .d.ts files in the dependency workspace source folder.

I have set up a project to showcase the behavior here.

Being able to able to run svelte-package with an option tsconfig would allow to separate the tsconfig for IDE code navigation from the build tsconfig, avoiding the issue above.
svelte-check also allows this option, so this would make things consistent

What do you think ?

[quentinderoubaix]

hi @benmccann @dummdidumm, a little reminder on this

[quentinderoubaix]

hi @benmccann @dummdidumm

sorry to chase again, is there anything I need to update / clarify for this ?
the linked issue #9373 was tagged as ready to implement, but maybe it needs to be re-discussed ?

[quentinderoubaix]

[dummdidumm]

Sorry for being silent for so long - I'm currently focused on Svelte 5. I'll look into this soon, I promise!

[dummdidumm]

Thank you!