Add info about product switching to Navigation page (Docs) (#520)

Author: devalog

fern/products/docs/pages/navigation/overview.mdx

@@ -252,3 +252,25 @@ layout:
 ## Versions
 
 If you have multiple versions of your documentation, you can introduce a dropdown version selector by specifying the `versions`. For more information, check out our [documentation on versioning](/learn/docs/building-your-docs/versioning).
+
+## Product switching
+
+If you have multiple products in your documentation, you can introduce a dropdown product selector by creating separate product configuration files. Each product can contain its own distinct versions, tabs, sections, pages, and API references, though products can also share content.
+
+<CodeBlock title="docs.yml">
+```yaml {2-3, 7-8}
+products:
+  - display-name: Product A
+    path: ./products/product-a.yml
+    icon: fa-solid fa-leaf # optional
+    slug: product-a # optional
+    subtitle: Product A subtitle # optional
+  - display-name: Product B
+    path: ./products/product-b/latest.yml # <-- default showing latest
+    image: ./images/product-b.png # optional
+    slug: product-b # optional
+    subtitle: Product B subtitle # optional
+```
+</CodeBlock>
+
+For more information about setting up this up, check out our [documentation on product switching](/learn/docs/configuration/products).