Next 3.0 Preview: Static Exports and Dynamic Imports

Introduced `next export` subcommand for building standalone static websites, enabling deployment without a server. This feature supports dynamic URLs, prefetching, preloading, and dynamic imports. Also introduced dynamic component support using `next/dynamic` and TC39 dynamic import syntax (`import()`) for lazy loading modules and improved code splitting, with server-side rendering capabilities for dynamic imports to avoid blank pages.