Add a library mode / packaging

[fabien-ml]

Hi,
It would be nice to have an option like the sveltekit package to allow people to create library without the pain to configure rollup or vite build config, add .d.ts files etc...

[ryansolid]

Interesting, so they force everything into src/lib and then get you to publish from a created subdirectory. Seems interesting also seems a bit fragile/restrictive. I can see the motivation. Let's add it to the list to explore but I don't see this as a primary goal currently.

[fabien-ml]

I've posted the issue here because in svelte it's in sveltekit but maybe a simple solid template with a pre made vite build.lib config could do the job.

I'm sure i'm not the only one that want to build a lib but doesn't know anything about rollup and "how to deploy a package", which js export format to use etc...😅