In short: The "stories" here are frontend components that are being rendered in isolation, with the ability to play with their params. It's also a nice way to document custom components in a project (this would be the "book" I guess). Storybook¹ is the mature project in this area.
As for Vite it's an alternative to Webpack which has gained rapid popularity - I've enjoyed using for its relatively light configuration and very fast live reloading support.
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¹https://storybook.js.org/ (much better landing page)