[docs] Add a CSS Modules to StyleX migration playbook

packages/docs/content/docs/llm-resources.mdx

@@ -14,9 +14,18 @@ Steps to install or integrate StyleX across Vite, Next.js, Webpack, Rspack, and
 
 <LLMInstallationFile />
 
-
 ## Style authoring guide
 
 Context on defining and using styles, StyleX APIs, and common antipatterns.
 
 <LLMStylingFile />
+
+## Migration guides
+
+Guides for LLM agents to migrate codebases from existing styling systems to
+StyleX while preserving behavior and clearly reporting anything that cannot be
+converted.
+
+### CSS Modules → StyleX
+
+<LLMMigrationFile />

packages/docs/src/components/mdx/LLMFiles.tsx

@@ -35,3 +35,14 @@ export function LLMStylingFile() {
     />
   );
 }
+
+export function LLMMigrationFile() {
+  const content = getFileContent('stylex-migration-css-modules.md');
+  return (
+    <ScrollableCodeBlock
+      content={content}
+      maxHeight={400}
+      title="stylex-migration-css-modules.md"
+    />
+  );
+}

packages/docs/src/components/mdx/index.tsx

@@ -25,7 +25,11 @@ import {
 import { Li, Ol, P, Ul } from './core';
 import Image from './Image';
 import { CodeBlock, Pre } from './CodeBlock';
-import { LLMInstallationFile, LLMStylingFile } from './LLMFiles';
+import {
+  LLMInstallationFile,
+  LLMMigrationFile,
+  LLMStylingFile,
+} from './LLMFiles';
 import { preMarker } from './mdx.stylex';
 import { vars } from '@/theming/vars.stylex';
 
@@ -92,6 +96,7 @@ export const mdxComponents = {
   ),
   CodeBlock,
   LLMInstallationFile,
+  LLMMigrationFile,
   LLMStylingFile,
 };