Storybook bloat? Fixed.

Storybook 9 addresses long-standing bloat criticism by cutting bundle size in half through strategic optimizations. The team consolidated packages, moved key addons into core, implemented aggressive prebundling to reduce dependency conflicts, and replaced heavy dependencies with lightweight alternatives like Polka instead of Express. A new minimal dev-only installation option further reduces footprint for users who don't need full features. These changes deliver faster installs, smaller lockfiles, and fewer upgrade issues while maintaining Storybook's comprehensive feature set.