chore(changeset): clarify breaking changes for imports/styles/unplugin and Node/PNPM requirements

Author: simonguo

.changeset/v3-major.md

@@ -18,3 +18,8 @@ BREAKING CHANGES:
 
 - `useCodeExecution` effect behavior stabilized; consumers relying on previous implicit re-execution may need to explicitly update `code` or pass `dependencies`
 - Package structure reorganized across `packages/*`; import paths may need updates according to exports
+
+- Imports: `CodeView` is now also a default export in `@react-code-view/react` and re-exported by `react-code-view`; prefer `import CodeView from 'react-code-view'` or adjust named imports accordingly
+- Styles: Less entries were removed; switch to `import 'react-code-view/styles'` and optional `import 'react-code-view/styles/highlight'`
+- Build integration: Legacy `webpack-md-loader` is removed; migrate to unified `@react-code-view/unplugin` for Vite/Webpack/Rollup/esbuild/Rspack
+- Tooling: Minimum requirements updated to Node >=18 and PNPM >=8 for the monorepo/dev workflow