fix: Prevent exported runtime stories from colliding with story names

[xeho91]

Resolves #250

[JReinhold]

I've confirmed that the failing test is indeed because Storybook's internal CSF parsing (that is used by the Vitest addon) has a bug where it does not get tags (like '!test') out from stories exported like export { localName as exportName }. That bug is fixed in storybookjs/storybook#31519

Thus making this change would mean that story-level 'test'/'!test' tags in Svelte CSF would not be picked up by addon-vitest until the bug is fixed in Storybook 9.0.0. I think we should wait with releasing this change to the addon until SB 9 goes stable then, but I wouldn't consider it a breaking change.
Thoughts @shilman ?

[shilman]

We could patch the fix back to 8.6 if it helps?

I'm doing an RC release in the next hour also FWIW

[JReinhold]

We could patch the fix back to 8.6 if it helps?

The addon supports 8.2 and up, so that wouldn't help that much in terms of breaking change. I think waiting till 9.0 GA is fine.

[JReinhold]

I updated the Storybook (and a bunch of other stuff) to include the fix and now the tests are passing. 🎉