[autofix.ci] apply automated fixes

Add compact documentation for previously undocumented bundler features:

**CLI Flags:**
- `--emit-dce-annotations` - Re-emit DCE annotations in output
- `--ignore-dce-annotations` - Ignore tree-shaking annotations
- `--css-chunking` - Chunk shared CSS across entry points
- `--server-components` - Enable React Server Components (experimental)

**JavaScript API:**
- `reactFastRefresh` - Enable React Fast Refresh for development
- `hotModuleReloading` - Enable HMR support

Features were verified against source code in src/cli/ and src/options.zig.
Documentation added to appropriate existing pages rather than creating new files.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

docs/bundler/css.md

@@ -5,6 +5,16 @@ Bun's bundler has built-in support for CSS with the following features:
 - CSS Modules
 - Tailwind (via a native bundler plugin)
 
+## CSS Chunking
+
+When multiple entry points import the same CSS files, use `--css-chunking` to reduce duplication by grouping shared CSS into separate chunks:
+
+```bash
+bun build ./home.ts ./about.ts --css-chunking --outdir ./dist
+```
+
+This creates separate CSS files for shared imports, reducing total CSS size in multi-page applications.
+
 ## Transpiling
 
 Bun's CSS bundler lets you use modern/future CSS features without having to worry about browser compatibility — all thanks to its transpiling and vendor prefixing features which are enabled by default.

docs/bundler/fullstack.md

@@ -174,6 +174,18 @@ export function App() {
 
 {% /codetabs %}
 
+### Server Components (Experimental)
+
+Enable React Server Components with `--server-components` (requires server-side target):
+
+```bash
+bun build ./app/page.tsx --server-components --target bun --outdir ./dist
+```
+
+{% callout %}
+Server Components support is experimental and the API may change.
+{% /callout %}
+
 ### Development mode
 
 When building locally, enable development mode by setting `development: true` in `Bun.serve()`.

docs/bundler/hmr.md

@@ -4,6 +4,18 @@ state and improves the development experience.
 
 HMR is enabled by default when using Bun's full-stack development server.
 
+## React Fast Refresh
+
+For React applications, enable React Fast Refresh for component-level hot reloading:
+
+```typescript
+await Bun.build({
+  entrypoints: ["./src/App.tsx"],
+  reactFastRefresh: true,
+  hotModuleReloading: true,
+});
+```
+
 ## `import.meta.hot` API Reference
 
 Bun implements a client-side HMR API modeled after [Vite's `import.meta.hot` API](https://vitejs.dev/guide/api-hmr.html). It can be checked for with `if (import.meta.hot)`, tree-shaking it in production

docs/bundler/index.md

@@ -773,9 +773,16 @@ $ bun build ./index.tsx --outdir ./out --minify-whitespace --minify-identifiers
 
 {% /codetabs %}
 
-<!-- ### `treeshaking`
+#### DCE annotations
 
-boolean; -->
+Control dead code elimination annotations like `@__PURE__`:
+
+- `--emit-dce-annotations` - Re-emit DCE annotations in output (default: enabled unless `--minify-whitespace`)
+- `--ignore-dce-annotations` - Ignore tree-shaking annotations
+
+```bash
+$ bun build ./index.tsx --ignore-dce-annotations --minify
+```
 
 ### `external`