add new readme guide

Author: devalog

fern/products/sdks/guides/configure-readme.mdx

@@ -0,0 +1,25 @@
+---
+title: Customize README
+description: Guide to configuring the README in your SDK
+---
+
+By default, the README for your SDKs is generated programmatically. You can override this by configuring the `readme` section in `generators.yml` to control the content and structure of generated README files across all your SDKs. 
+You can add custom introductions, showcase key endpoints, and organize your SDK documentation with feature sections.
+
+```yaml title="generators.yml"
+readme:
+  introduction: "Welcome to our API"
+  apiReferenceLink: "https://docs.example.com"
+  defaultEndpoint:
+    method: "POST"
+    path: "/users"
+  features:
+    authentication:
+      - method: "POST"
+        path: "/auth/login"
+    users:
+      - method: "GET"
+        path: "/users"
+```    
+
+For more detailed information on `readme` configuration, see the [`generators.yml` documentation](/sdks/reference/generators-yml#readme)

fern/products/sdks/reference/generators-yml-reference.mdx

@@ -108,13 +108,9 @@ api:
     - openapi: ./path/to/openapi
       headers: 
         X-Version: 
-          name: version # codegen name of the variable
-          type: literal<"1234"> # type of the header, in this case a literal
+          name: version # The variable name to use in generated SDK code. If not specified, uses the header name.
+          type: literal<"1234"> # The type of the header value for code generation (e.g., "string", "literal<'value'>", "number").
   ```
-
-  For advanced configuration objects:
-  - `name` (string): The variable name to use in generated SDK code. If not specified, uses the header name.
-  - `type` (string): The type of the header value for code generation (e.g., "string", "literal<'value'>", "number").
 </ParamField>
 
 <ParamField path="environments" type="EnvironmentsSchema" toc={true}>

fern/products/sdks/sdks.yml

@@ -202,6 +202,9 @@ navigation:
       - page: Filter Your Endpoints (Audiences)
         path: ./guides/filter-your-endpoints-audiences.mdx
         slug: audiences
+      - page: Customize the README for your SDKs
+        path: ./guides/configure-readme.mdx
+        slug: readme
       - page: Self-host Fern's SDK Generators
         hidden: true
         path: ./guides/self-host-fern-generators.mdx