Support Storybook config directory

[askoufis]

For reasons outlined in my PR comment, as well as an internal confluence document, leaning into the standard .storybook configuration folder rather than pointing into sku's node modules addresses some issues and reduces the complexity of sku's storybook integration.

This includes:

• Remove the symlinking shenanigans for preview config. Users can just write the file if they need it.
• Remove the dummy middleware file. Users can just require/copy/symlink their existing sku dev middleware to .storybook if they want it to run during sku storybook.
• Adds support for other config files that sku did not support

Sku still maintains control over the .storybook/main.js file as this contains critical configuration that enables storybook to work with sku's wepback setup, VE, TypeScript, etc.

This has been tested internally in both a regular app and an app within a monorepo.

[changeset-bot]

🦋 Changeset detected

Latest commit: 419d53a

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

This PR includes changesets to release 1 package

Name	Type
sku	Minor

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR