CSF: Use __namedExportsOrder array in loader if provided

[daKmoR]

closes #9136
follow up of #9181

What I did

As discussed in #9181 there have been 2 solutions to guarantee a story order if loaded via es modules. I went for the object. However, I have been missing the use case of rexports

const myStory = () => html`Foo`;
export { myStory as notMyStory };

which currently produces the following export const __orderedExports = { notMyStory }; which fails as notMyStory is not a local variable.

Therefore we should go with the previously discussed array of strings.

This Pull Request changes how loaders can guarantee the order of stories

Before:

export const __orderedExports = { notMyStory };

After:

export const __namedExportsOrder = ['notMyStory'];

How to test

• use storybook without webpack and provide this export

Notes

Related PR where we found the issue
open-wc/open-wc#1171

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[shilman]

LGTM